fix(#871): Recent Packets API — always return hash + timestamp (root cause of #857)

Root cause: enrichObs() looked up the parent transmission via byTxID,
but if the tx had been evicted from memory, the lookup returned nil and
hash/payload_type/route_type/decoded_json were omitted from the response.

Fix:
- enrichObs: fall back to DB lookup (GetTransmissionByID) when the
  in-memory tx is missing, ensuring hash and all tx fields are always
  present in the response
- GetNodeHealth recentPackets: defensive filter skips entries with nil
  hash or timestamp (belt-and-suspenders)
- Observer analytics recentPackets: skip entries missing hash
- Nil-safe: no panic when store has no DB reference

Tests: 4 new tests covering the DB fallback, nil-DB edge case, and
GetNodeHealth field invariants.

Closes #871
Refs #857

.github/workflows/deploy.yml

@@ -290,6 +290,10 @@ jobs:
         if: github.event_name == 'push'
         uses: docker/setup-buildx-action@v3
 
+      - name: Set up QEMU (arm64 runtime stage)
+        if: github.event_name == 'push'
+        uses: docker/setup-qemu-action@v3
+
       - name: Log in to GHCR
         if: github.event_name == 'push'
         uses: docker/login-action@v3
@@ -317,7 +321,7 @@ jobs:
         with:
           context: .
           push: true
-          platforms: linux/amd64
+          platforms: linux/amd64,linux/arm64
           tags: ${{ steps.docker-meta.outputs.tags }}
           labels: ${{ steps.docker-meta.outputs.labels }}
           build-args: |
@@ -387,7 +391,10 @@ jobs:
 
       - name: Deploy staging
         run: |
-          # Stop old container and release memory
+          # Force-remove the staging container regardless of how it was created
+          # (compose-managed OR manually created via docker run)
+          docker stop corescope-staging-go 2>/dev/null || true
+          docker rm -f corescope-staging-go 2>/dev/null || true
           docker compose -f "$STAGING_COMPOSE_FILE" -p corescope-staging down --timeout 30 2>/dev/null || true
 
           # Wait for container to be fully gone and OS to reclaim memory (3GB limit)
@@ -429,10 +436,11 @@ jobs:
 
       - name: Smoke test staging API
         run: |
-          if curl -sf http://localhost:82/api/stats | grep -q engine; then
+          PORT="${STAGING_GO_HTTP_PORT:-80}"
+          if curl -sf "http://localhost:${PORT}/api/stats" | grep -q engine; then
             echo "Staging verified — engine field present ✅"
           else
-            echo "Staging /api/stats did not return engine field"
+            echo "Staging /api/stats did not return engine field (port ${PORT})"
             exit 1
           fi
 

Dockerfile

@@ -1,19 +1,23 @@
-FROM golang:1.22-alpine AS builder
-
-RUN apk add --no-cache build-base
+# Build stage always runs natively on the builder's arch ($BUILDPLATFORM)
+# and cross-compiles to $TARGETOS/$TARGETARCH via Go toolchain. No QEMU.
+FROM --platform=$BUILDPLATFORM golang:1.22-alpine AS builder
 
 ARG APP_VERSION=unknown
 ARG GIT_COMMIT=unknown
 ARG BUILD_TIME=unknown
+# Provided by buildx for multi-arch builds
+ARG TARGETOS
+ARG TARGETARCH
 
-# Build server
+# Build server (pure-Go sqlite — no CGO needed, cross-compiles cleanly)
 WORKDIR /build/server
 COPY cmd/server/go.mod cmd/server/go.sum ./
 COPY internal/geofilter/ ../../internal/geofilter/
 COPY internal/sigvalidate/ ../../internal/sigvalidate/
 RUN go mod download
 COPY cmd/server/ ./
-RUN go build -ldflags "-X main.Version=${APP_VERSION} -X main.Commit=${GIT_COMMIT} -X main.BuildTime=${BUILD_TIME}" -o /corescope-server .
+RUN CGO_ENABLED=0 GOOS=${TARGETOS} GOARCH=${TARGETARCH} \
+    go build -ldflags "-X main.Version=${APP_VERSION} -X main.Commit=${GIT_COMMIT} -X main.BuildTime=${BUILD_TIME}" -o /corescope-server .
 
 # Build ingestor
 WORKDIR /build/ingestor
@@ -22,7 +26,8 @@ COPY internal/geofilter/ ../../internal/geofilter/
 COPY internal/sigvalidate/ ../../internal/sigvalidate/
 RUN go mod download
 COPY cmd/ingestor/ ./
-RUN go build -o /corescope-ingestor .
+RUN CGO_ENABLED=0 GOOS=${TARGETOS} GOARCH=${TARGETARCH} \
+    go build -o /corescope-ingestor .
 
 # Build decrypt CLI
 WORKDIR /build/decrypt
@@ -30,7 +35,8 @@ COPY cmd/decrypt/go.mod cmd/decrypt/go.sum ./
 COPY internal/channel/ ../../internal/channel/
 RUN go mod download
 COPY cmd/decrypt/ ./
-RUN CGO_ENABLED=0 go build -ldflags="-s -w" -o /corescope-decrypt .
+RUN CGO_ENABLED=0 GOOS=${TARGETOS} GOARCH=${TARGETARCH} \
+    go build -ldflags="-s -w" -o /corescope-decrypt .
 
 # Runtime image
 FROM alpine:3.20

cmd/ingestor/config.go

@@ -39,7 +39,8 @@ type Config struct {
 	HashChannels    []string          `json:"hashChannels,omitempty"`
 	Retention       *RetentionConfig  `json:"retention,omitempty"`
 	Metrics         *MetricsConfig    `json:"metrics,omitempty"`
-	GeoFilter       *GeoFilterConfig  `json:"geo_filter,omitempty"`
+	GeoFilter            *GeoFilterConfig  `json:"geo_filter,omitempty"`
+	ValidateSignatures   *bool             `json:"validateSignatures,omitempty"`
 }
 
 // GeoFilterConfig is an alias for the shared geofilter.Config type.
@@ -47,8 +48,9 @@ type GeoFilterConfig = geofilter.Config
 
 // RetentionConfig controls how long stale nodes are kept before being moved to inactive_nodes.
 type RetentionConfig struct {
-	NodeDays    int `json:"nodeDays"`
-	MetricsDays int `json:"metricsDays"`
+	NodeDays      int `json:"nodeDays"`
+	ObserverDays  int `json:"observerDays"`
+	MetricsDays   int `json:"metricsDays"`
 }
 
 // MetricsConfig controls observer metrics collection.
@@ -56,6 +58,14 @@ type MetricsConfig struct {
 	SampleIntervalSec int `json:"sampleIntervalSec"`
 }
 
+// ShouldValidateSignatures returns true (default) unless explicitly disabled.
+func (c *Config) ShouldValidateSignatures() bool {
+	if c.ValidateSignatures != nil {
+		return *c.ValidateSignatures
+	}
+	return true
+}
+
 // MetricsSampleInterval returns the configured sample interval or 300s default.
 func (c *Config) MetricsSampleInterval() int {
 	if c.Metrics != nil && c.Metrics.SampleIntervalSec > 0 {
@@ -80,6 +90,15 @@ func (c *Config) NodeDaysOrDefault() int {
 	return 7
 }
 
+// ObserverDaysOrDefault returns the configured retention.observerDays or 14 if not set.
+// A value of -1 means observers are never removed.
+func (c *Config) ObserverDaysOrDefault() int {
+	if c.Retention != nil && c.Retention.ObserverDays != 0 {
+		return c.Retention.ObserverDays
+	}
+	return 14
+}
+
 // LoadConfig reads configuration from a JSON file, with env var overrides.
 // If the config file does not exist, sensible defaults are used (zero-config startup).
 func LoadConfig(path string) (*Config, error) {

cmd/ingestor/coverage_boost_test.go

@@ -6,6 +6,7 @@ import (
 	"encoding/hex"
 	"encoding/json"
 	"testing"
+	"time"
 )
 
 // hmacSHA256 computes HMAC-SHA256 for test use.
@@ -157,7 +158,7 @@ func TestHandleMessageChannelMessage(t *testing.T) {
 	payload := []byte(`{"text":"Alice: Hello everyone","channel_idx":3,"SNR":5.0,"RSSI":-95,"score":10,"direction":"rx","sender_timestamp":1700000000}`)
 	msg := &mockMessage{topic: "meshcore/message/channel/2", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -217,7 +218,7 @@ func TestHandleMessageChannelMessageEmptyText(t *testing.T) {
 	store, source := newTestContext(t)
 
 	msg := &mockMessage{topic: "meshcore/message/channel/1", payload: []byte(`{"text":""}`)}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -232,7 +233,7 @@ func TestHandleMessageChannelNoSender(t *testing.T) {
 	store, source := newTestContext(t)
 
 	msg := &mockMessage{topic: "meshcore/message/channel/1", payload: []byte(`{"text":"no sender here"}`)}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM nodes").Scan(&count); err != nil {
@@ -249,7 +250,7 @@ func TestHandleMessageDirectMessage(t *testing.T) {
 	payload := []byte(`{"text":"Bob: Hey there","sender_timestamp":1700000000,"SNR":3.0,"rssi":-100,"Score":8,"Direction":"tx"}`)
 	msg := &mockMessage{topic: "meshcore/message/direct/abc123", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -293,7 +294,7 @@ func TestHandleMessageDirectMessageEmptyText(t *testing.T) {
 	store, source := newTestContext(t)
 
 	msg := &mockMessage{topic: "meshcore/message/direct/abc", payload: []byte(`{"text":""}`)}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -308,7 +309,7 @@ func TestHandleMessageDirectNoSender(t *testing.T) {
 	store, source := newTestContext(t)
 
 	msg := &mockMessage{topic: "meshcore/message/direct/xyz", payload: []byte(`{"text":"message with no colon"}`)}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -327,7 +328,7 @@ func TestHandleMessageUppercaseScoreDirection(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `","Score":9.0,"Direction":"tx"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var score *float64
 	var direction *string
@@ -348,7 +349,7 @@ func TestHandleMessageChannelLowercaseFields(t *testing.T) {
 
 	payload := []byte(`{"text":"Test: msg","snr":3.0,"rssi":-90,"Score":5,"Direction":"rx"}`)
 	msg := &mockMessage{topic: "meshcore/message/channel/0", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -364,7 +365,7 @@ func TestHandleMessageDirectLowercaseFields(t *testing.T) {
 
 	payload := []byte(`{"text":"Test: msg","snr":2.0,"rssi":-85,"score":7,"direction":"tx"}`)
 	msg := &mockMessage{topic: "meshcore/message/direct/xyz", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -387,7 +388,7 @@ func TestHandleMessageAdvertWithTelemetry(t *testing.T) {
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	// Should have created transmission, node, and observer
 	var txCount, nodeCount, obsCount int
@@ -427,7 +428,7 @@ func TestHandleMessageAdvertGeoFiltered(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, gf)
+	handleMessage(store, "test", source, msg, nil, &Config{GeoFilter: gf})
 
 	// Geo-filtered adverts should not create nodes
 	var nodeCount int
@@ -664,7 +665,7 @@ func TestHandleMessageCorruptedAdvertNoNode(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM nodes").Scan(&count); err != nil {
@@ -686,7 +687,7 @@ func TestHandleMessageNonAdvertPacket(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -863,7 +864,7 @@ func TestHandleMessageChannelLongSender(t *testing.T) {
 	longText := "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA: msg"
 	payload := []byte(`{"text":"` + longText + `"}`)
 	msg := &mockMessage{topic: "meshcore/message/channel/1", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM nodes").Scan(&count); err != nil {
@@ -882,7 +883,7 @@ func TestHandleMessageDirectLongSender(t *testing.T) {
 	longText := "BBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBBB: msg"
 	payload := []byte(`{"text":"` + longText + `"}`)
 	msg := &mockMessage{topic: "meshcore/message/direct/abc", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -899,7 +900,7 @@ func TestHandleMessageDirectUppercaseScoreDirection(t *testing.T) {
 
 	payload := []byte(`{"text":"X: hi","Score":6,"Direction":"rx"}`)
 	msg := &mockMessage{topic: "meshcore/message/direct/d1", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -929,7 +930,7 @@ func TestHandleMessageChannelUppercaseScoreDirection(t *testing.T) {
 
 	payload := []byte(`{"text":"Y: hi","Score":4,"Direction":"tx"}`)
 	msg := &mockMessage{topic: "meshcore/message/channel/5", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count); err != nil {
@@ -960,7 +961,7 @@ func TestHandleMessageRawLowercaseScore(t *testing.T) {
 	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
 	payload := []byte(`{"raw":"` + rawHex + `","score":3.5}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var score *float64
 	if err := store.db.QueryRow("SELECT score FROM observations LIMIT 1").Scan(&score); err != nil {
@@ -979,7 +980,7 @@ func TestHandleMessageStatusNoOrigin(t *testing.T) {
 		topic:   "meshcore/LAX/obs5/status",
 		payload: []byte(`{"model":"L1"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	if err := store.db.QueryRow("SELECT COUNT(*) FROM observers WHERE id = 'obs5'").Scan(&count); err != nil {
@@ -1138,3 +1139,182 @@ func TestDecodeTraceWithPath(t *testing.T) {
 		t.Errorf("flags=%v, want 3", p.TraceFlags)
 	}
 }
+
+// --- db.go: RemoveStaleObservers (soft-delete) ---
+
+func TestRemoveStaleObservers(t *testing.T) {
+	store := newTestStore(t)
+
+	// Insert an observer with last_seen 30 days ago
+	err := store.UpsertObserver("obs-old", "OldObserver", "LAX", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	// Override last_seen to 30 days ago
+	cutoff := time.Now().UTC().AddDate(0, 0, -30).Format(time.RFC3339)
+	_, err = store.db.Exec("UPDATE observers SET last_seen = ? WHERE id = ?", cutoff, "obs-old")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Insert a recent observer
+	err = store.UpsertObserver("obs-new", "NewObserver", "NYC", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	removed, err := store.RemoveStaleObservers(14)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if removed != 1 {
+		t.Errorf("removed=%d, want 1", removed)
+	}
+
+	// Observer should still be in the table (soft-delete), but marked inactive
+	var count int
+	if err := store.db.QueryRow("SELECT COUNT(*) FROM observers").Scan(&count); err != nil {
+		t.Fatal(err)
+	}
+	if count != 2 {
+		t.Errorf("observers count=%d, want 2 (soft-delete preserves row)", count)
+	}
+
+	// Check that the old observer is marked inactive
+	var inactive int
+	if err := store.db.QueryRow("SELECT inactive FROM observers WHERE id = ?", "obs-old").Scan(&inactive); err != nil {
+		t.Fatal(err)
+	}
+	if inactive != 1 {
+		t.Errorf("obs-old inactive=%d, want 1", inactive)
+	}
+
+	// Check that the recent observer is still active
+	var newInactive int
+	if err := store.db.QueryRow("SELECT inactive FROM observers WHERE id = ?", "obs-new").Scan(&newInactive); err != nil {
+		t.Fatal(err)
+	}
+	if newInactive != 0 {
+		t.Errorf("obs-new inactive=%d, want 0", newInactive)
+	}
+}
+
+func TestRemoveStaleObserversNone(t *testing.T) {
+	store := newTestStore(t)
+
+	removed, err := store.RemoveStaleObservers(14)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if removed != 0 {
+		t.Errorf("removed=%d, want 0", removed)
+	}
+}
+
+func TestRemoveStaleObserversKeepForever(t *testing.T) {
+	store := newTestStore(t)
+
+	// Insert an old observer
+	err := store.UpsertObserver("obs-ancient", "AncientObserver", "LAX", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cutoff := time.Now().UTC().AddDate(0, 0, -365).Format(time.RFC3339)
+	_, err = store.db.Exec("UPDATE observers SET last_seen = ? WHERE id = ?", cutoff, "obs-ancient")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// observerDays = -1 means keep forever
+	removed, err := store.RemoveStaleObservers(-1)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if removed != 0 {
+		t.Errorf("removed=%d, want 0 (keep forever)", removed)
+	}
+
+	var count int
+	if err := store.db.QueryRow("SELECT COUNT(*) FROM observers").Scan(&count); err != nil {
+		t.Fatal(err)
+	}
+	if count != 1 {
+		t.Errorf("observers count=%d, want 1 (keep forever)", count)
+	}
+
+	// Observer should NOT be marked inactive
+	var inactive int
+	if err := store.db.QueryRow("SELECT inactive FROM observers WHERE id = ?", "obs-ancient").Scan(&inactive); err != nil {
+		t.Fatal(err)
+	}
+	if inactive != 0 {
+		t.Errorf("obs-ancient inactive=%d, want 0 (keep forever)", inactive)
+	}
+}
+
+func TestRemoveStaleObserversReactivation(t *testing.T) {
+	store := newTestStore(t)
+
+	// Insert and stale-mark an observer
+	err := store.UpsertObserver("obs-test", "TestObserver", "LAX", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cutoff := time.Now().UTC().AddDate(0, 0, -30).Format(time.RFC3339)
+	_, err = store.db.Exec("UPDATE observers SET last_seen = ? WHERE id = ?", cutoff, "obs-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	removed, err := store.RemoveStaleObservers(14)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if removed != 1 {
+		t.Errorf("removed=%d, want 1", removed)
+	}
+
+	// Verify it's inactive
+	var inactive int
+	if err := store.db.QueryRow("SELECT inactive FROM observers WHERE id = ?", "obs-test").Scan(&inactive); err != nil {
+		t.Fatal(err)
+	}
+	if inactive != 1 {
+		t.Errorf("inactive=%d, want 1 after soft-delete", inactive)
+	}
+
+	// Now UpsertObserver should reactivate it
+	err = store.UpsertObserver("obs-test", "TestObserver", "LAX", nil)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := store.db.QueryRow("SELECT inactive FROM observers WHERE id = ?", "obs-test").Scan(&inactive); err != nil {
+		t.Fatal(err)
+	}
+	if inactive != 0 {
+		t.Errorf("inactive=%d, want 0 after reactivation", inactive)
+	}
+}
+
+func TestObserverDaysOrDefault(t *testing.T) {
+	tests := []struct {
+		name string
+		cfg  *Config
+		want int
+	}{
+		{"nil retention", &Config{}, 14},
+		{"zero observer days", &Config{Retention: &RetentionConfig{ObserverDays: 0}}, 14},
+		{"positive value", &Config{Retention: &RetentionConfig{ObserverDays: 30}}, 30},
+		{"keep forever", &Config{Retention: &RetentionConfig{ObserverDays: -1}}, -1},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := tt.cfg.ObserverDaysOrDefault()
+			if got != tt.want {
+				t.Errorf("ObserverDaysOrDefault() = %d, want %d", got, tt.want)
+			}
+		})
+	}
+}

cmd/ingestor/db.go

@@ -22,6 +22,7 @@ type DBStats struct {
 	NodeUpserts            atomic.Int64
 	ObserverUpserts        atomic.Int64
 	WriteErrors            atomic.Int64
+	SignatureDrops         atomic.Int64
 }
 
 // Store wraps the SQLite database for packet ingestion.
@@ -110,7 +111,8 @@ func applySchema(db *sql.DB) error {
 			radio TEXT,
 			battery_mv INTEGER,
 			uptime_secs INTEGER,
-			noise_floor REAL
+			noise_floor REAL,
+			inactive INTEGER DEFAULT 0
 		);
 
 		CREATE INDEX IF NOT EXISTS idx_nodes_last_seen ON nodes(last_seen);
@@ -195,7 +197,7 @@ func applySchema(db *sql.DB) error {
 				   t.created_at
 			FROM observations o
 			JOIN transmissions t ON t.id = o.transmission_id
-			LEFT JOIN observers obs ON obs.rowid = o.observer_idx
+			LEFT JOIN observers obs ON obs.rowid = o.observer_idx AND (obs.inactive IS NULL OR obs.inactive = 0)
 	`)
 	if vErr != nil {
 		return fmt.Errorf("packets_v view: %w", vErr)
@@ -335,6 +337,19 @@ func applySchema(db *sql.DB) error {
 		log.Println("[migration] observer_metrics timestamp index created")
 	}
 
+	// Migration: add inactive column to observers for soft-delete retention
+	row = db.QueryRow("SELECT 1 FROM _migrations WHERE name = 'observers_inactive_v1'")
+	if row.Scan(&migDone) != nil {
+		log.Println("[migration] Adding inactive column to observers...")
+		_, err := db.Exec(`ALTER TABLE observers ADD COLUMN inactive INTEGER DEFAULT 0`)
+		if err != nil {
+			// Column may already exist (e.g. fresh install with schema above)
+			log.Printf("[migration] observers.inactive: %v (may already exist)", err)
+		}
+		db.Exec(`INSERT INTO _migrations (name) VALUES ('observers_inactive_v1')`)
+		log.Println("[migration] observers.inactive column added")
+	}
+
 	// Migration: add packets_sent and packets_recv columns to observer_metrics
 	row = db.QueryRow("SELECT 1 FROM _migrations WHERE name = 'observer_metrics_packets_v1'")
 	if row.Scan(&migDone) != nil {
@@ -345,6 +360,54 @@ func applySchema(db *sql.DB) error {
 		log.Println("[migration] packets_sent/packets_recv columns added")
 	}
 
+	// Migration: add channel_hash column for fast channel queries (#762)
+	row = db.QueryRow("SELECT 1 FROM _migrations WHERE name = 'channel_hash_v1'")
+	if row.Scan(&migDone) != nil {
+		log.Println("[migration] Adding channel_hash column to transmissions...")
+		db.Exec(`ALTER TABLE transmissions ADD COLUMN channel_hash TEXT DEFAULT NULL`)
+		db.Exec(`CREATE INDEX IF NOT EXISTS idx_tx_channel_hash ON transmissions(channel_hash) WHERE payload_type = 5`)
+		// Backfill: extract channel name for decrypted (CHAN) packets
+		res, err := db.Exec(`UPDATE transmissions SET channel_hash = json_extract(decoded_json, '$.channel') WHERE payload_type = 5 AND channel_hash IS NULL AND json_extract(decoded_json, '$.type') = 'CHAN'`)
+		if err == nil {
+			n, _ := res.RowsAffected()
+			log.Printf("[migration] Backfilled channel_hash for %d CHAN packets", n)
+		}
+		// Backfill: extract channelHashHex for encrypted (GRP_TXT) packets, prefixed with 'enc_'
+		res, err = db.Exec(`UPDATE transmissions SET channel_hash = 'enc_' || json_extract(decoded_json, '$.channelHashHex') WHERE payload_type = 5 AND channel_hash IS NULL AND json_extract(decoded_json, '$.type') = 'GRP_TXT'`)
+		if err == nil {
+			n, _ := res.RowsAffected()
+			log.Printf("[migration] Backfilled channel_hash for %d GRP_TXT packets", n)
+		}
+		db.Exec(`INSERT INTO _migrations (name) VALUES ('channel_hash_v1')`)
+		log.Println("[migration] channel_hash column added and backfilled")
+	}
+
+	// Migration: dropped_packets table for signature validation failures (#793)
+	row = db.QueryRow("SELECT 1 FROM _migrations WHERE name = 'dropped_packets_v1'")
+	if row.Scan(&migDone) != nil {
+		log.Println("[migration] Creating dropped_packets table...")
+		_, err := db.Exec(`
+			CREATE TABLE IF NOT EXISTS dropped_packets (
+				id INTEGER PRIMARY KEY AUTOINCREMENT,
+				hash TEXT,
+				raw_hex TEXT,
+				reason TEXT NOT NULL,
+				observer_id TEXT,
+				observer_name TEXT,
+				node_pubkey TEXT,
+				node_name TEXT,
+				dropped_at DATETIME DEFAULT CURRENT_TIMESTAMP
+			);
+			CREATE INDEX IF NOT EXISTS idx_dropped_observer ON dropped_packets(observer_id);
+			CREATE INDEX IF NOT EXISTS idx_dropped_node ON dropped_packets(node_pubkey);
+		`)
+		if err != nil {
+			return fmt.Errorf("dropped_packets schema: %w", err)
+		}
+		db.Exec(`INSERT INTO _migrations (name) VALUES ('dropped_packets_v1')`)
+		log.Println("[migration] dropped_packets table created")
+	}
+
 	return nil
 }
 
@@ -357,8 +420,8 @@ func (s *Store) prepareStatements() error {
 	}
 
 	s.stmtInsertTransmission, err = s.db.Prepare(`
-		INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, payload_version, decoded_json)
-		VALUES (?, ?, ?, ?, ?, ?, ?)
+		INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, payload_version, decoded_json, channel_hash)
+		VALUES (?, ?, ?, ?, ?, ?, ?, ?)
 	`)
 	if err != nil {
 		return err
@@ -370,8 +433,12 @@ func (s *Store) prepareStatements() error {
 	}
 
 	s.stmtInsertObservation, err = s.db.Prepare(`
-		INSERT OR IGNORE INTO observations (transmission_id, observer_idx, direction, snr, rssi, score, path_json, timestamp)
+		INSERT INTO observations (transmission_id, observer_idx, direction, snr, rssi, score, path_json, timestamp)
 		VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+		ON CONFLICT(transmission_id, observer_idx, COALESCE(path_json, '')) DO UPDATE SET
+			snr   = COALESCE(excluded.snr,   snr),
+			rssi  = COALESCE(excluded.rssi,  rssi),
+			score = COALESCE(excluded.score, score)
 	`)
 	if err != nil {
 		return err
@@ -481,7 +548,7 @@ func (s *Store) InsertTransmission(data *PacketData) (bool, error) {
 		result, err := s.stmtInsertTransmission.Exec(
 			data.RawHex, hash, now,
 			data.RouteType, data.PayloadType, data.PayloadVersion,
-			data.DecodedJSON,
+			data.DecodedJSON, nilIfEmpty(data.ChannelHash),
 		)
 		if err != nil {
 			s.Stats.WriteErrors.Add(1)
@@ -622,10 +689,13 @@ func (s *Store) UpsertObserver(id, name, iata string, meta *ObserverMeta) error
 	)
 	if err != nil {
 		s.Stats.WriteErrors.Add(1)
-	} else {
-		s.Stats.ObserverUpserts.Add(1)
+		return err
 	}
-	return err
+	s.Stats.ObserverUpserts.Add(1)
+
+	// Reactivate if this observer was previously marked inactive
+	s.db.Exec(`UPDATE observers SET inactive = 0 WHERE id = ? AND inactive = 1`, id)
+	return nil
 }
 
 // Close checkpoints the WAL and closes the database.
@@ -719,13 +789,14 @@ func (s *Store) Checkpoint() {
 
 // LogStats logs current operational metrics.
 func (s *Store) LogStats() {
-	log.Printf("[stats] tx_inserted=%d tx_dupes=%d obs_inserted=%d node_upserts=%d observer_upserts=%d write_errors=%d",
+	log.Printf("[stats] tx_inserted=%d tx_dupes=%d obs_inserted=%d node_upserts=%d observer_upserts=%d write_errors=%d sig_drops=%d",
 		s.Stats.TransmissionsInserted.Load(),
 		s.Stats.DuplicateTransmissions.Load(),
 		s.Stats.ObservationsInserted.Load(),
 		s.Stats.NodeUpserts.Load(),
 		s.Stats.ObserverUpserts.Load(),
 		s.Stats.WriteErrors.Load(),
+		s.Stats.SignatureDrops.Load(),
 	)
 }
 
@@ -757,6 +828,71 @@ func (s *Store) MoveStaleNodes(nodeDays int) (int64, error) {
 	return moved, nil
 }
 
+// RemoveStaleObservers marks observers that have not actively sent data in observerDays
+// as inactive (soft-delete). This preserves JOIN integrity for observations.observer_idx
+// and observer_metrics.observer_id — historical data still references the correct observer.
+// An observer must actively send data to stay listed — being seen by another node does not count.
+// observerDays <= -1 means never remove (keep forever).
+func (s *Store) RemoveStaleObservers(observerDays int) (int64, error) {
+	if observerDays <= -1 {
+		return 0, nil // keep forever
+	}
+	cutoff := time.Now().UTC().AddDate(0, 0, -observerDays).Format(time.RFC3339)
+	result, err := s.db.Exec(`UPDATE observers SET inactive = 1 WHERE last_seen < ? AND (inactive IS NULL OR inactive = 0)`, cutoff)
+	if err != nil {
+		return 0, fmt.Errorf("mark stale observers inactive: %w", err)
+	}
+	removed, _ := result.RowsAffected()
+	if removed > 0 {
+		// Clean up orphaned metrics for now-inactive observers
+		s.db.Exec(`DELETE FROM observer_metrics WHERE observer_id IN (SELECT id FROM observers WHERE inactive = 1)`)
+		log.Printf("Marked %d observer(s) as inactive (not seen in %d days)", removed, observerDays)
+	}
+	return removed, nil
+}
+
+// DroppedPacket holds data for a packet rejected during ingest.
+type DroppedPacket struct {
+	Hash         string
+	RawHex       string
+	Reason       string
+	ObserverID   string
+	ObserverName string
+	NodePubKey   string
+	NodeName     string
+}
+
+// InsertDroppedPacket records a rejected packet in the dropped_packets table.
+func (s *Store) InsertDroppedPacket(dp *DroppedPacket) error {
+	_, err := s.db.Exec(
+		`INSERT INTO dropped_packets (hash, raw_hex, reason, observer_id, observer_name, node_pubkey, node_name) VALUES (?, ?, ?, ?, ?, ?, ?)`,
+		dp.Hash, dp.RawHex, dp.Reason, dp.ObserverID, dp.ObserverName, dp.NodePubKey, dp.NodeName,
+	)
+	if err != nil {
+		s.Stats.WriteErrors.Add(1)
+		return fmt.Errorf("insert dropped packet: %w", err)
+	}
+	s.Stats.SignatureDrops.Add(1)
+	return nil
+}
+
+// PruneDroppedPackets removes dropped_packets older than retentionDays.
+func (s *Store) PruneDroppedPackets(retentionDays int) (int64, error) {
+	if retentionDays <= 0 {
+		return 0, nil
+	}
+	cutoff := time.Now().UTC().AddDate(0, 0, -retentionDays).Format(time.RFC3339)
+	result, err := s.db.Exec(`DELETE FROM dropped_packets WHERE dropped_at < ?`, cutoff)
+	if err != nil {
+		return 0, fmt.Errorf("prune dropped packets: %w", err)
+	}
+	n, _ := result.RowsAffected()
+	if n > 0 {
+		log.Printf("Pruned %d dropped packet(s) older than %d days", n, retentionDays)
+	}
+	return n, nil
+}
+
 // PacketData holds the data needed to insert a packet into the DB.
 type PacketData struct {
 	RawHex         string
@@ -773,6 +909,15 @@ type PacketData struct {
 	PayloadVersion int
 	PathJSON       string
 	DecodedJSON    string
+	ChannelHash    string // grouping key for channel queries (#762)
+}
+
+// nilIfEmpty returns nil for empty strings (for nullable DB columns).
+func nilIfEmpty(s string) interface{} {
+	if s == "" {
+		return nil
+	}
+	return s
 }
 
 // MQTTPacketMessage is the JSON payload from an MQTT raw packet message.
@@ -794,7 +939,7 @@ func BuildPacketData(msg *MQTTPacketMessage, decoded *DecodedPacket, observerID,
 		pathJSON = string(b)
 	}
 
-	return &PacketData{
+	pd := &PacketData{
 		RawHex:         msg.Raw,
 		Timestamp:      now,
 		ObserverID:     observerID,
@@ -810,4 +955,15 @@ func BuildPacketData(msg *MQTTPacketMessage, decoded *DecodedPacket, observerID,
 		PathJSON:       pathJSON,
 		DecodedJSON:    PayloadJSON(&decoded.Payload),
 	}
+
+	// Populate channel_hash for fast channel queries (#762)
+	if decoded.Header.PayloadType == PayloadGRP_TXT {
+		if decoded.Payload.Type == "CHAN" && decoded.Payload.Channel != "" {
+			pd.ChannelHash = decoded.Payload.Channel
+		} else if decoded.Payload.Type == "GRP_TXT" && decoded.Payload.ChannelHashHex != "" {
+			pd.ChannelHash = "enc_" + decoded.Payload.ChannelHashHex
+		}
+	}
+
+	return pd
 }

cmd/ingestor/db_test.go

@@ -1882,3 +1882,89 @@ func TestExtractObserverMetaNewFields(t *testing.T) {
 		t.Errorf("RecvErrors = %v, want 3", meta.RecvErrors)
 	}
 }
+
+// TestInsertObservationSNRFillIn verifies that when the same observation is
+// received twice — first without SNR, then with SNR — the SNR is filled in
+// rather than silently discarded. The unique dedup index is
+// (transmission_id, observer_idx, COALESCE(path_json, '')); observer_idx must
+// be non-NULL for the conflict to fire (SQLite treats NULL != NULL).
+func TestInsertObservationSNRFillIn(t *testing.T) {
+	s, err := OpenStore(tempDBPath(t))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer s.Close()
+
+	// Register the observer so observer_idx is non-NULL (required for dedup).
+	if err := s.UpsertObserver("pymc-obs1", "PyMC Observer", "SJC", nil); err != nil {
+		t.Fatal(err)
+	}
+
+	// First arrival: same observer, no SNR/RSSI (e.g. broker replay without RF fields).
+	data1 := &PacketData{
+		RawHex:     "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976",
+		Timestamp:  "2026-04-20T00:00:00Z",
+		Hash:       "snrfillin0001hash",
+		RouteType:  1,
+		ObserverID: "pymc-obs1",
+		SNR:        nil,
+		RSSI:       nil,
+	}
+	if _, err := s.InsertTransmission(data1); err != nil {
+		t.Fatal(err)
+	}
+
+	var snr1, rssi1 *float64
+	s.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr1, &rssi1)
+	if snr1 != nil || rssi1 != nil {
+		t.Fatalf("precondition: first insert should have nil SNR/RSSI, got snr=%v rssi=%v", snr1, rssi1)
+	}
+
+	// Second arrival: same packet, same observer, now WITH SNR/RSSI.
+	snr := 10.5
+	rssi := -88.0
+	data2 := &PacketData{
+		RawHex:     data1.RawHex,
+		Timestamp:  data1.Timestamp,
+		Hash:       data1.Hash,
+		RouteType:  data1.RouteType,
+		ObserverID: "pymc-obs1",
+		SNR:        &snr,
+		RSSI:       &rssi,
+	}
+	if _, err := s.InsertTransmission(data2); err != nil {
+		t.Fatal(err)
+	}
+
+	var snr2, rssi2 *float64
+	s.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr2, &rssi2)
+	if snr2 == nil || *snr2 != snr {
+		t.Errorf("SNR not filled in by second arrival: got %v, want %v", snr2, snr)
+	}
+	if rssi2 == nil || *rssi2 != rssi {
+		t.Errorf("RSSI not filled in by second arrival: got %v, want %v", rssi2, rssi)
+	}
+
+	// Third arrival: same packet again, SNR absent — must NOT overwrite existing SNR.
+	data3 := &PacketData{
+		RawHex:     data1.RawHex,
+		Timestamp:  data1.Timestamp,
+		Hash:       data1.Hash,
+		RouteType:  data1.RouteType,
+		ObserverID: "pymc-obs1",
+		SNR:        nil,
+		RSSI:       nil,
+	}
+	if _, err := s.InsertTransmission(data3); err != nil {
+		t.Fatal(err)
+	}
+
+	var snr3, rssi3 *float64
+	s.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr3, &rssi3)
+	if snr3 == nil || *snr3 != snr {
+		t.Errorf("SNR overwritten by null arrival: got %v, want %v", snr3, snr)
+	}
+	if rssi3 == nil || *rssi3 != rssi {
+		t.Errorf("RSSI overwritten by null arrival: got %v, want %v", rssi3, rssi)
+	}
+}

cmd/ingestor/decoder.go

@@ -80,9 +80,10 @@ type TransportCodes struct {
 
 // Path holds decoded path/hop information.
 type Path struct {
-	HashSize  int      `json:"hashSize"`
-	HashCount int      `json:"hashCount"`
-	Hops      []string `json:"hops"`
+	HashSize      int      `json:"hashSize"`
+	HashCount     int      `json:"hashCount"`
+	Hops          []string `json:"hops"`
+	HopsCompleted *int     `json:"hopsCompleted,omitempty"`
 }
 
 // AdvertFlags holds decoded advert flag bits.
@@ -143,6 +144,7 @@ type DecodedPacket struct {
 	Path           Path            `json:"path"`
 	Payload        Payload         `json:"payload"`
 	Raw            string          `json:"raw"`
+	Anomaly        string          `json:"anomaly,omitempty"`
 }
 
 func decodeHeader(b byte) Header {
@@ -586,17 +588,35 @@ func DecodePacket(hexString string, channelKeys map[string]string, validateSigna
 	payload := decodePayload(header.PayloadType, payloadBuf, channelKeys, validateSignatures)
 
 	// TRACE packets store hop IDs in the payload (buf[9:]) rather than the header
-	// path field. The header path byte still encodes hashSize in bits 6-7, which
-	// we use to split the payload path data into individual hop prefixes.
+	// path field. Firmware always sends TRACE as DIRECT (route_type 2 or 3);
+	// FLOOD-routed TRACEs are anomalous but handled gracefully (parsed, but
+	// flagged). The TRACE flags byte (payload offset 8) encodes path_sz in
+	// bits 0-1 as a power-of-two exponent: hash_bytes = 1 << path_sz.
+	// NOT the header path byte's hash_size bits. The header path contains SNR
+	// bytes — one per hop that actually forwarded.
+	// We expose hopsCompleted (count of SNR bytes) so consumers can distinguish
+	// how far the trace got vs the full intended route.
+	var anomaly string
 	if header.PayloadType == PayloadTRACE && payload.PathData != "" {
+		// Flag anomalous routing — firmware only sends TRACE as DIRECT
+		if header.RouteType != RouteDirect && header.RouteType != RouteTransportDirect {
+			anomaly = "TRACE packet with non-DIRECT routing (expected DIRECT or TRANSPORT_DIRECT)"
+		}
+		// The header path hops count represents SNR entries = completed hops
+		hopsCompleted := path.HashCount
 		pathBytes, err := hex.DecodeString(payload.PathData)
-		if err == nil && path.HashSize > 0 {
-			hops := make([]string, 0, len(pathBytes)/path.HashSize)
-			for i := 0; i+path.HashSize <= len(pathBytes); i += path.HashSize {
-				hops = append(hops, strings.ToUpper(hex.EncodeToString(pathBytes[i:i+path.HashSize])))
+		if err == nil && payload.TraceFlags != nil {
+			// path_sz from flags byte is a power-of-two exponent per firmware:
+			// hash_bytes = 1 << (flags & 0x03)
+			pathSz := 1 << (*payload.TraceFlags & 0x03)
+			hops := make([]string, 0, len(pathBytes)/pathSz)
+			for i := 0; i+pathSz <= len(pathBytes); i += pathSz {
+				hops = append(hops, strings.ToUpper(hex.EncodeToString(pathBytes[i:i+pathSz])))
 			}
 			path.Hops = hops
 			path.HashCount = len(hops)
+			path.HashSize = pathSz
+			path.HopsCompleted = &hopsCompleted
 		}
 	}
 
@@ -616,12 +636,14 @@ func DecodePacket(hexString string, channelKeys map[string]string, validateSigna
 		Path:           path,
 		Payload:        payload,
 		Raw:            strings.ToUpper(hexString),
+		Anomaly:        anomaly,
 	}, nil
 }
 
 // ComputeContentHash computes the SHA-256-based content hash (first 16 hex chars).
-// It hashes the header byte + payload (skipping path bytes) to produce a
-// path-independent identifier for the same transmission.
+// It hashes the payload-type nibble + payload (skipping path bytes) to produce a
+// route-independent identifier for the same logical packet. For TRACE packets,
+// path_len is included in the hash to match firmware behavior.
 func ComputeContentHash(rawHex string) string {
 	buf, err := hex.DecodeString(rawHex)
 	if err != nil || len(buf) < 2 {
@@ -657,7 +679,18 @@ func ComputeContentHash(rawHex string) string {
 	}
 
 	payload := buf[payloadStart:]
-	toHash := append([]byte{headerByte}, payload...)
+
+	// Hash payload-type byte only (bits 2-5 of header), not the full header.
+	// Firmware: SHA256(payload_type + [path_len for TRACE] + payload)
+	// Using the full header caused different hashes for the same logical packet
+	// when route type or version bits differed. See issue #786.
+	payloadType := (headerByte >> 2) & 0x0F
+	toHash := []byte{payloadType}
+	if int(payloadType) == PayloadTRACE {
+		// Firmware uses uint16_t path_len (2 bytes, little-endian)
+		toHash = append(toHash, pathByte, 0x00)
+	}
+	toHash = append(toHash, payload...)
 
 	h := sha256.Sum256(toHash)
 	return hex.EncodeToString(h[:])[:16]

cmd/ingestor/decoder_test.go

@@ -926,6 +926,93 @@ func TestComputeContentHashLongFallback(t *testing.T) {
 	}
 }
 
+// TestComputeContentHashRouteTypeIndependence verifies that the same logical
+// packet produces the same content hash regardless of route type (issue #786).
+func TestComputeContentHashRouteTypeIndependence(t *testing.T) {
+	// Same payload type (TXT_MSG=2, bits 2-5) with different route types.
+	// Header 0x08 = route_type 0 (TRANSPORT_FLOOD), payload_type 2
+	// Header 0x0A = route_type 2 (DIRECT), payload_type 2
+	// Header 0x09 = route_type 1 (FLOOD), payload_type 2
+	// pathByte=0x00, payload=D69FD7A5A7
+	payloadHex := "D69FD7A5A7"
+
+	// FLOOD: header=0x09 (route_type 1), pathByte=0x00
+	floodHex := "09" + "00" + payloadHex
+	// DIRECT: header=0x0A (route_type 2), pathByte=0x00
+	directHex := "0A" + "00" + payloadHex
+
+	hashFlood := ComputeContentHash(floodHex)
+	hashDirect := ComputeContentHash(directHex)
+	if hashFlood != hashDirect {
+		t.Errorf("same payload with different route types produced different hashes: flood=%s direct=%s", hashFlood, hashDirect)
+	}
+}
+
+// TestComputeContentHashTraceIncludesPathLen verifies TRACE packets include
+// path_len in the hash (matching firmware behavior).
+func TestComputeContentHashTraceIncludesPathLen(t *testing.T) {
+	// TRACE = payload_type 0x09, so header bits 2-5 = 0x09 → header = 0x09<<2 | route=2 = 0x26
+	// pathByte=0x01 (1 hop, 1-byte hash) → 1 path byte
+	traceHeader1 := "26" // route=2, payload_type=9
+	pathByte1 := "01"
+	pathData1 := "AA"
+	payload := "DEADBEEF"
+	hex1 := traceHeader1 + pathByte1 + pathData1 + payload
+
+	// Same but pathByte=0x02 (2 hops) → 2 path bytes
+	pathByte2 := "02"
+	pathData2 := "AABB"
+	hex2 := traceHeader1 + pathByte2 + pathData2 + payload
+
+	hash1 := ComputeContentHash(hex1)
+	hash2 := ComputeContentHash(hex2)
+	if hash1 == hash2 {
+		t.Error("TRACE packets with different path_len should produce different hashes (path_len is part of hash input)")
+	}
+}
+
+// TestComputeContentHashMatchesFirmware verifies hash output matches what the
+// firmware would compute: SHA256(payload_type_byte + payload)[:16hex].
+func TestComputeContentHashMatchesFirmware(t *testing.T) {
+	// header=0x0A → payload_type = (0x0A >> 2) & 0x0F = 2
+	// pathByte=0x00, payload = D69FD7A5A7475DB07337749AE61FA53A4788E976
+	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
+	hash := ComputeContentHash(rawHex)
+
+	// Manually compute expected: SHA256(0x02 + payload_bytes)
+	payloadBytes, _ := hex.DecodeString("D69FD7A5A7475DB07337749AE61FA53A4788E976")
+	toHash := append([]byte{0x02}, payloadBytes...)
+	expected := sha256.Sum256(toHash)
+	expectedHex := hex.EncodeToString(expected[:])[:16]
+	if hash != expectedHex {
+		t.Errorf("hash=%s, want %s (firmware-compatible)", hash, expectedHex)
+	}
+}
+
+// TestComputeContentHashTraceGoldenValue is a golden-value test that locks down
+// the 2-byte path_len (uint16 LE) behavior for TRACE hashing. If anyone removes
+// the 0x00 byte from the hash input, this test breaks.
+//
+// Packet: header=0x25 (FLOOD route=1, payload_type=TRACE=0x09), pathByte=0x02
+// (2 hops, 1-byte hash), path=[AA,BB], payload=[DE,AD,BE,EF].
+// Hash input: [0x09, 0x02, 0x00, 0xDE, 0xAD, 0xBE, 0xEF]
+//   → SHA256 = b1baaf3bf0d0726c2672b1ec9e2665dc...
+//   → first 16 hex chars = "b1baaf3bf0d0726c"
+func TestComputeContentHashTraceGoldenValue(t *testing.T) {
+	// TRACE packet: header byte 0x25 = payload_type 9 (TRACE), route_type 1 (FLOOD)
+	// pathByte 0x02 = hash_size 1, hash_count 2
+	// 2 path bytes (AA, BB), then payload DEADBEEF
+	rawHex := "2502AABBDEADBEEF"
+	hash := ComputeContentHash(rawHex)
+
+	// Pre-computed: SHA256(0x09 0x02 0x00 0xDE 0xAD 0xBE 0xEF)[:16hex]
+	// The 0x00 is the high byte of uint16_t path_len (little-endian).
+	const golden = "b1baaf3bf0d0726c"
+	if hash != golden {
+		t.Errorf("TRACE golden hash = %s, want %s (2-byte path_len encoding)", hash, golden)
+	}
+}
+
 func TestDecodePacketWithWhitespace(t *testing.T) {
 	raw := "0A 00 D6 9F D7 A5 A7 47 5D B0 73 37 74 9A E6 1F A5 3A 47 88 E9 76"
 	pkt, err := DecodePacket(raw, nil, false)

cmd/ingestor/main.go

@@ -61,9 +61,14 @@ func main() {
 	nodeDays := cfg.NodeDaysOrDefault()
 	store.MoveStaleNodes(nodeDays)
 
+	// Observer retention: remove stale observers on startup
+	observerDays := cfg.ObserverDaysOrDefault()
+	store.RemoveStaleObservers(observerDays)
+
 	// Metrics retention: prune old metrics on startup
 	metricsDays := cfg.MetricsRetentionDays()
 	store.PruneOldMetrics(metricsDays)
+	store.PruneDroppedPackets(metricsDays)
 
 	// Daily ticker for node retention
 	retentionTicker := time.NewTicker(1 * time.Hour)
@@ -73,11 +78,22 @@ func main() {
 		}
 	}()
 
+	// Daily ticker for observer retention (every 24h, staggered 90s after startup)
+	observerRetentionTicker := time.NewTicker(24 * time.Hour)
+	go func() {
+		time.Sleep(90 * time.Second) // stagger after metrics prune
+		store.RemoveStaleObservers(observerDays)
+		for range observerRetentionTicker.C {
+			store.RemoveStaleObservers(observerDays)
+		}
+	}()
+
 	// Daily ticker for metrics retention (every 24h)
 	metricsRetentionTicker := time.NewTicker(24 * time.Hour)
 	go func() {
 		for range metricsRetentionTicker.C {
 			store.PruneOldMetrics(metricsDays)
+			store.PruneDroppedPackets(metricsDays)
 		}
 	}()
 
@@ -146,7 +162,7 @@ func main() {
 		// Capture source for closure
 		src := source
 		opts.SetDefaultPublishHandler(func(c mqtt.Client, m mqtt.Message) {
-			handleMessage(store, tag, src, m, channelKeys, cfg.GeoFilter)
+			handleMessage(store, tag, src, m, channelKeys, cfg)
 		})
 
 		client := mqtt.NewClient(opts)
@@ -181,7 +197,7 @@ func main() {
 	log.Println("Done.")
 }
 
-func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message, channelKeys map[string]string, geoFilter *GeoFilterConfig) {
+func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message, channelKeys map[string]string, cfg *Config) {
 	defer func() {
 		if r := recover(); r != nil {
 			log.Printf("MQTT [%s] panic in handler: %v", tag, r)
@@ -191,21 +207,6 @@ func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message,
 	topic := m.Topic()
 	parts := strings.Split(topic, "/")
 
-	// IATA filter
-	if len(source.IATAFilter) > 0 && len(parts) > 1 {
-		region := parts[1]
-		matched := false
-		for _, f := range source.IATAFilter {
-			if f == region {
-				matched = true
-				break
-			}
-		}
-		if !matched {
-			return
-		}
-	}
-
 	var msg map[string]interface{}
 	if err := json.Unmarshal(m.Payload(), &msg); err != nil {
 		return
@@ -217,6 +218,9 @@ func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message,
 	}
 
 	// Status topic: meshcore/<region>/<observer_id>/status
+	// IATA filter does NOT apply here — observer metadata (noise_floor, battery, etc.)
+	// is region-independent and should be accepted from all observers regardless of
+	// which IATA regions are configured for packet ingestion.
 	if len(parts) >= 4 && parts[3] == "status" {
 		observerID := parts[2]
 		name, _ := msg["origin"].(string)
@@ -245,10 +249,26 @@ func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message,
 		return
 	}
 
+	// IATA filter applies to packet messages only — not status messages above.
+	if len(source.IATAFilter) > 0 && len(parts) > 1 {
+		region := parts[1]
+		matched := false
+		for _, f := range source.IATAFilter {
+			if f == region {
+				matched = true
+				break
+			}
+		}
+		if !matched {
+			return
+		}
+	}
+
 	// Format 1: Raw packet (meshcoretomqtt / Cisien format)
 	rawHex, _ := msg["raw"].(string)
 	if rawHex != "" {
-		decoded, err := DecodePacket(rawHex, channelKeys, false)
+		validateSigs := cfg.ShouldValidateSignatures()
+		decoded, err := DecodePacket(rawHex, channelKeys, validateSigs)
 		if err != nil {
 			log.Printf("MQTT [%s] decode error: %v", tag, err)
 			return
@@ -308,7 +328,27 @@ func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message,
 				log.Printf("MQTT [%s] skipping corrupted ADVERT: %s", tag, reason)
 				return
 			}
-			if !NodePassesGeoFilter(decoded.Payload.Lat, decoded.Payload.Lon, geoFilter) {
+			// Signature validation: drop adverts with invalid ed25519 signatures
+			if validateSigs && decoded.Payload.SignatureValid != nil && !*decoded.Payload.SignatureValid {
+				hash := ComputeContentHash(rawHex)
+				truncPK := decoded.Payload.PubKey
+				if len(truncPK) > 16 {
+					truncPK = truncPK[:16]
+				}
+				log.Printf("MQTT [%s] DROPPED invalid signature: hash=%s name=%s observer=%s pubkey=%s",
+					tag, hash, decoded.Payload.Name, firstNonEmpty(mqttMsg.Origin, observerID), truncPK)
+				store.InsertDroppedPacket(&DroppedPacket{
+					Hash:         hash,
+					RawHex:       rawHex,
+					Reason:       "invalid signature",
+					ObserverID:   observerID,
+					ObserverName: mqttMsg.Origin,
+					NodePubKey:   decoded.Payload.PubKey,
+					NodeName:     decoded.Payload.Name,
+				})
+				return
+			}
+			if !NodePassesGeoFilter(decoded.Payload.Lat, decoded.Payload.Lon, cfg.GeoFilter) {
 				return
 			}
 			pktData := BuildPacketData(mqttMsg, decoded, observerID, region)
@@ -440,6 +480,7 @@ func handleMessage(store *Store, tag string, source MQTTSource, m mqtt.Message,
 			PayloadType:  5, // GRP_TXT
 			PathJSON:     "[]",
 			DecodedJSON:  string(decodedJSON),
+			ChannelHash:  channelName, // fast channel queries (#762)
 		}
 
 		if _, err := store.InsertTransmission(pktData); err != nil {

cmd/ingestor/main_test.go

@@ -130,7 +130,7 @@ func TestHandleMessageRawPacket(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `","SNR":5.5,"RSSI":-100.0,"origin":"myobs"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -147,7 +147,7 @@ func TestHandleMessageRawPacketAdvert(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	// Should create a node from the ADVERT
 	var count int
@@ -169,7 +169,7 @@ func TestHandleMessageInvalidJSON(t *testing.T) {
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: []byte(`not json`)}
 
 	// Should not panic
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -186,7 +186,7 @@ func TestHandleMessageStatusTopic(t *testing.T) {
 		payload: []byte(`{"origin":"MyObserver"}`),
 	}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var name, iata string
 	err := store.db.QueryRow("SELECT name, iata FROM observers WHERE id = 'obs1'").Scan(&name, &iata)
@@ -207,11 +207,11 @@ func TestHandleMessageSkipStatusTopics(t *testing.T) {
 
 	// meshcore/status should be skipped
 	msg1 := &mockMessage{topic: "meshcore/status", payload: []byte(`{"raw":"0A00"}`)}
-	handleMessage(store, "test", source, msg1, nil, nil)
+	handleMessage(store, "test", source, msg1, nil, &Config{})
 
 	// meshcore/events/connection should be skipped
 	msg2 := &mockMessage{topic: "meshcore/events/connection", payload: []byte(`{"raw":"0A00"}`)}
-	handleMessage(store, "test", source, msg2, nil, nil)
+	handleMessage(store, "test", source, msg2, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -230,7 +230,7 @@ func TestHandleMessageIATAFilter(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -243,7 +243,7 @@ func TestHandleMessageIATAFilter(t *testing.T) {
 		topic:   "meshcore/LAX/obs2/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg2, nil, nil)
+	handleMessage(store, "test", source, msg2, nil, &Config{})
 
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
 	if count != 1 {
@@ -261,7 +261,7 @@ func TestHandleMessageIATAFilterNoRegion(t *testing.T) {
 		topic:   "meshcore",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	// No region part → filter doesn't apply, message goes through
 	// Actually the code checks len(parts) > 1 for IATA filter
@@ -277,7 +277,7 @@ func TestHandleMessageNoRawHex(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"type":"companion","data":"something"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -295,7 +295,7 @@ func TestHandleMessageBadRawHex(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"ZZZZ"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -312,7 +312,7 @@ func TestHandleMessageWithSNRRSSIAsNumbers(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `","SNR":7.2,"RSSI":-95}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var snr, rssi *float64
 	store.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr, &rssi)
@@ -331,7 +331,7 @@ func TestHandleMessageMinimalTopic(t *testing.T) {
 		topic:   "meshcore/SJC",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -352,7 +352,7 @@ func TestHandleMessageCorruptedAdvert(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/packets",
 		payload: []byte(`{"raw":"` + rawHex + `"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	// Transmission should be inserted (even if advert is invalid)
 	var count int
@@ -378,7 +378,7 @@ func TestHandleMessageNoObserverID(t *testing.T) {
 		topic:   "packets",
 		payload: []byte(`{"raw":"` + rawHex + `","origin":"obs1"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -400,7 +400,7 @@ func TestHandleMessageSNRNotFloat(t *testing.T) {
 	// SNR as a string value — should not parse as float
 	payload := []byte(`{"raw":"` + rawHex + `","SNR":"bad","RSSI":"bad"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var count int
 	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
@@ -416,7 +416,7 @@ func TestHandleMessageOriginExtraction(t *testing.T) {
 	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
 	payload := []byte(`{"raw":"` + rawHex + `","origin":"MyOrigin"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	// Verify origin was extracted to observer name
 	var name string
@@ -439,7 +439,7 @@ func TestHandleMessagePanicRecovery(t *testing.T) {
 	}
 
 	// Should not panic — the defer/recover should catch it
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 }
 
 func TestHandleMessageStatusOriginFallback(t *testing.T) {
@@ -451,7 +451,7 @@ func TestHandleMessageStatusOriginFallback(t *testing.T) {
 		topic:   "meshcore/SJC/obs1/status",
 		payload: []byte(`{"type":"status"}`),
 	}
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var name string
 	err := store.db.QueryRow("SELECT name FROM observers WHERE id = 'obs1'").Scan(&name)
@@ -640,7 +640,7 @@ func TestHandleMessageWithLowercaseSNRRSSI(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `","snr":5.5,"rssi":-102}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var snr, rssi *float64
 	store.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr, &rssi)
@@ -661,7 +661,7 @@ func TestHandleMessageSNRRSSIUppercaseWins(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `","SNR":7.2,"snr":1.0,"RSSI":-95,"rssi":-50}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var snr, rssi *float64
 	store.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr, &rssi)
@@ -681,7 +681,7 @@ func TestHandleMessageNoSNRRSSI(t *testing.T) {
 	payload := []byte(`{"raw":"` + rawHex + `"}`)
 	msg := &mockMessage{topic: "meshcore/SJC/obs1/packets", payload: payload}
 
-	handleMessage(store, "test", source, msg, nil, nil)
+	handleMessage(store, "test", source, msg, nil, &Config{})
 
 	var snr, rssi *float64
 	store.db.QueryRow("SELECT snr, rssi FROM observations LIMIT 1").Scan(&snr, &rssi)
@@ -739,3 +739,44 @@ func TestToFloat64WithUnits(t *testing.T) {
 		}
 	}
 }
+
+// TestIATAFilterDoesNotDropStatusMessages verifies that status messages from
+// out-of-region observers are still processed (noise_floor, battery, etc.)
+// even when an IATA filter is configured for packet data.
+func TestIATAFilterDoesNotDropStatusMessages(t *testing.T) {
+	store := newTestStore(t)
+	source := MQTTSource{Name: "test", IATAFilter: []string{"SJC"}}
+
+	// BFL observer sends a status message with noise_floor — outside the IATA filter.
+	msg := &mockMessage{
+		topic:   "meshcore/BFL/bfl-obs1/status",
+		payload: []byte(`{"origin":"BFLObserver","stats":{"noise_floor":-105.0}}`),
+	}
+	handleMessage(store, "test", source, msg, nil, &Config{})
+
+	var name string
+	var noiseFloor *float64
+	err := store.db.QueryRow("SELECT name, noise_floor FROM observers WHERE id = 'bfl-obs1'").Scan(&name, &noiseFloor)
+	if err != nil {
+		t.Fatalf("observer not found after status from out-of-region observer: %v", err)
+	}
+	if name != "BFLObserver" {
+		t.Errorf("name=%q, want BFLObserver", name)
+	}
+	if noiseFloor == nil || *noiseFloor != -105.0 {
+		t.Errorf("noise_floor=%v, want -105.0 — status message was dropped by IATA filter when it should not be", noiseFloor)
+	}
+
+	// Verify that a packet from BFL is still filtered.
+	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
+	pktMsg := &mockMessage{
+		topic:   "meshcore/BFL/bfl-obs1/packets",
+		payload: []byte(`{"raw":"` + rawHex + `"}`),
+	}
+	handleMessage(store, "test", source, pktMsg, nil, &Config{})
+	var count int
+	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
+	if count != 0 {
+		t.Error("packet from out-of-region BFL should still be filtered by IATA")
+	}
+}

cmd/ingestor/sig_validate_ingest_test.go

@@ -0,0 +1,339 @@
+package main
+
+import (
+	"crypto/ed25519"
+	"encoding/binary"
+	"encoding/hex"
+	"strings"
+	"testing"
+)
+
+// buildAdvertHex constructs a full ADVERT packet hex string.
+// header(1) + pathByte(1) + pubkey(32) + timestamp(4) + signature(64) + appdata
+func buildAdvertHex(pubKey ed25519.PublicKey, privKey ed25519.PrivateKey, timestamp uint32, appdata []byte) string {
+	// Build signed message: pubkey(32) + timestamp(4 LE) + appdata
+	msg := make([]byte, 32+4+len(appdata))
+	copy(msg[0:32], pubKey)
+	binary.LittleEndian.PutUint32(msg[32:36], timestamp)
+	copy(msg[36:], appdata)
+
+	sig := ed25519.Sign(privKey, msg)
+
+	// Payload: pubkey(32) + timestamp(4) + signature(64) + appdata
+	payload := make([]byte, 0, 100+len(appdata))
+	payload = append(payload, pubKey...)
+	ts := make([]byte, 4)
+	binary.LittleEndian.PutUint32(ts, timestamp)
+	payload = append(payload, ts...)
+	payload = append(payload, sig...)
+	payload = append(payload, appdata...)
+
+	// Header: ADVERT (0x04 << 2) | FLOOD (1) = 0x11, pathByte=0 (no hops)
+	header := byte(0x11)
+	pathByte := byte(0x00)
+
+	pkt := append([]byte{header, pathByte}, payload...)
+	return hex.EncodeToString(pkt)
+}
+
+// makeAppdata builds minimal appdata: flags(1) + name
+func makeAppdata(name string) []byte {
+	flags := byte(0x81) // hasName=true, type=companion(1)
+	data := []byte{flags}
+	data = append(data, []byte(name)...)
+	data = append(data, 0x00) // null terminator
+	return data
+}
+
+func TestSigValidation_ValidAdvertStored(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	appdata := makeAppdata("TestNode")
+	rawHex := buildAdvertHex(pub, priv, 1700000000, appdata)
+
+	source := MQTTSource{Name: "test"}
+	msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+rawHex+`","origin":"TestObs"}`)
+	cfg := &Config{}
+
+	handleMessage(store, "test", source, msg, nil, cfg)
+
+	// Verify packet was stored
+	var count int
+	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&count)
+	if count == 0 {
+		t.Fatal("valid advert should be stored, got 0 transmissions")
+	}
+}
+
+func TestSigValidation_TamperedSignatureDropped(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	appdata := makeAppdata("BadNode")
+	rawHex := buildAdvertHex(pub, priv, 1700000000, appdata)
+
+	// Tamper with signature (flip a byte in the signature area)
+	// Signature starts at offset 2 (header+path) + 32 (pubkey) + 4 (timestamp) = 38
+	// That's byte 38 in the packet, hex chars 76-77
+	rawBytes := []byte(rawHex)
+	if rawBytes[76] == '0' {
+		rawBytes[76] = 'f'
+	} else {
+		rawBytes[76] = '0'
+	}
+	tamperedHex := string(rawBytes)
+
+	source := MQTTSource{Name: "test"}
+	msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+tamperedHex+`","origin":"TestObs"}`)
+	cfg := &Config{}
+
+	handleMessage(store, "test", source, msg, nil, cfg)
+
+	// Verify packet was NOT stored in transmissions
+	var txCount int
+	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&txCount)
+	if txCount != 0 {
+		t.Fatalf("tampered advert should be dropped, got %d transmissions", txCount)
+	}
+
+	// Verify it was recorded in dropped_packets
+	var dropCount int
+	store.db.QueryRow("SELECT COUNT(*) FROM dropped_packets").Scan(&dropCount)
+	if dropCount == 0 {
+		t.Fatal("tampered advert should be recorded in dropped_packets")
+	}
+
+	// Verify drop counter incremented
+	if store.Stats.SignatureDrops.Load() != 1 {
+		t.Fatalf("expected 1 signature drop, got %d", store.Stats.SignatureDrops.Load())
+	}
+
+	// Verify dropped_packets has correct fields
+	var reason, nodeKey, nodeName, obsID string
+	store.db.QueryRow("SELECT reason, node_pubkey, node_name, observer_id FROM dropped_packets LIMIT 1").Scan(&reason, &nodeKey, &nodeName, &obsID)
+	if reason != "invalid signature" {
+		t.Fatalf("expected reason 'invalid signature', got %q", reason)
+	}
+	if nodeKey == "" {
+		t.Fatal("dropped packet should have node_pubkey")
+	}
+	if !strings.Contains(nodeName, "BadNode") {
+		t.Fatalf("expected node_name to contain 'BadNode', got %q", nodeName)
+	}
+	if obsID != "obs1" {
+		t.Fatalf("expected observer_id 'obs1', got %q", obsID)
+	}
+}
+
+func TestSigValidation_TruncatedAppdataDropped(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	appdata := makeAppdata("TruncNode")
+	rawHex := buildAdvertHex(pub, priv, 1700000000, appdata)
+
+	// Sign was computed with full appdata. Now truncate the raw hex to remove
+	// some appdata bytes, making the signature invalid.
+	// Truncate last 4 hex chars (2 bytes of appdata)
+	truncatedHex := rawHex[:len(rawHex)-4]
+
+	source := MQTTSource{Name: "test"}
+	msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+truncatedHex+`","origin":"TestObs"}`)
+	cfg := &Config{}
+
+	handleMessage(store, "test", source, msg, nil, cfg)
+
+	var txCount int
+	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&txCount)
+	if txCount != 0 {
+		t.Fatalf("truncated advert should be dropped, got %d transmissions", txCount)
+	}
+}
+
+func TestSigValidation_DisabledByConfig(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	appdata := makeAppdata("NoValNode")
+	rawHex := buildAdvertHex(pub, priv, 1700000000, appdata)
+
+	// Tamper with signature
+	rawBytes := []byte(rawHex)
+	if rawBytes[76] == '0' {
+		rawBytes[76] = 'f'
+	} else {
+		rawBytes[76] = '0'
+	}
+	tamperedHex := string(rawBytes)
+
+	source := MQTTSource{Name: "test"}
+	msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+tamperedHex+`","origin":"TestObs"}`)
+	falseVal := false
+	cfg := &Config{ValidateSignatures: &falseVal}
+
+	handleMessage(store, "test", source, msg, nil, cfg)
+
+	// With validation disabled, tampered packet should be stored
+	var txCount int
+	store.db.QueryRow("SELECT COUNT(*) FROM transmissions").Scan(&txCount)
+	if txCount == 0 {
+		t.Fatal("with validateSignatures=false, tampered advert should be stored")
+	}
+}
+
+func TestSigValidation_DropCounterIncrements(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	source := MQTTSource{Name: "test"}
+	cfg := &Config{}
+
+	for i := 0; i < 3; i++ {
+		appdata := makeAppdata("Node")
+		rawHex := buildAdvertHex(pub, priv, uint32(1700000000+i), appdata)
+		// Tamper
+		rawBytes := []byte(rawHex)
+		if rawBytes[76] == '0' {
+			rawBytes[76] = 'f'
+		} else {
+			rawBytes[76] = '0'
+		}
+		msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+string(rawBytes)+`","origin":"Obs"}`)
+		handleMessage(store, "test", source, msg, nil, cfg)
+	}
+
+	if store.Stats.SignatureDrops.Load() != 3 {
+		t.Fatalf("expected 3 signature drops, got %d", store.Stats.SignatureDrops.Load())
+	}
+}
+
+func TestSigValidation_LogContainsFields(t *testing.T) {
+	// This test verifies the dropped_packets row has all required fields
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	pub, priv, _ := ed25519.GenerateKey(nil)
+	appdata := makeAppdata("LogTestNode")
+	rawHex := buildAdvertHex(pub, priv, 1700000000, appdata)
+
+	// Tamper
+	rawBytes := []byte(rawHex)
+	if rawBytes[76] == '0' {
+		rawBytes[76] = 'f'
+	} else {
+		rawBytes[76] = '0'
+	}
+
+	source := MQTTSource{Name: "test"}
+	msg := newMockMsg("meshcore/US/obs1/packet", `{"raw":"`+string(rawBytes)+`","origin":"MyObserver"}`)
+	cfg := &Config{}
+
+	handleMessage(store, "test", source, msg, nil, cfg)
+
+	var hash, reason, obsID, obsName, pubkey, nodeName string
+	err = store.db.QueryRow("SELECT hash, reason, observer_id, observer_name, node_pubkey, node_name FROM dropped_packets LIMIT 1").
+		Scan(&hash, &reason, &obsID, &obsName, &pubkey, &nodeName)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if hash == "" {
+		t.Error("dropped packet should have hash")
+	}
+	if reason != "invalid signature" {
+		t.Errorf("expected reason 'invalid signature', got %q", reason)
+	}
+	if obsID != "obs1" {
+		t.Errorf("expected observer_id 'obs1', got %q", obsID)
+	}
+	if obsName != "MyObserver" {
+		t.Errorf("expected observer_name 'MyObserver', got %q", obsName)
+	}
+	if pubkey == "" {
+		t.Error("dropped packet should have node_pubkey")
+	}
+	if !strings.Contains(nodeName, "LogTestNode") {
+		t.Errorf("expected node_name containing 'LogTestNode', got %q", nodeName)
+	}
+}
+
+func TestPruneDroppedPackets(t *testing.T) {
+	dbPath := t.TempDir() + "/test.db"
+	store, err := OpenStoreWithInterval(dbPath, 300)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer store.Close()
+
+	// Insert an old dropped packet
+	store.db.Exec(`INSERT INTO dropped_packets (hash, reason, dropped_at) VALUES ('old', 'test', datetime('now', '-60 days'))`)
+	store.db.Exec(`INSERT INTO dropped_packets (hash, reason, dropped_at) VALUES ('new', 'test', datetime('now'))`)
+
+	n, err := store.PruneDroppedPackets(30)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 1 {
+		t.Fatalf("expected 1 pruned, got %d", n)
+	}
+
+	var count int
+	store.db.QueryRow("SELECT COUNT(*) FROM dropped_packets").Scan(&count)
+	if count != 1 {
+		t.Fatalf("expected 1 remaining, got %d", count)
+	}
+}
+
+func TestShouldValidateSignatures_Default(t *testing.T) {
+	cfg := &Config{}
+	if !cfg.ShouldValidateSignatures() {
+		t.Fatal("default should be true")
+	}
+
+	falseVal := false
+	cfg2 := &Config{ValidateSignatures: &falseVal}
+	if cfg2.ShouldValidateSignatures() {
+		t.Fatal("explicit false should be false")
+	}
+
+	trueVal := true
+	cfg3 := &Config{ValidateSignatures: &trueVal}
+	if !cfg3.ShouldValidateSignatures() {
+		t.Fatal("explicit true should be true")
+	}
+}
+
+// newMockMsg creates a minimal mqtt.Message for testing.
+func newMockMsg(topic, payload string) *mockMessage {
+	return &mockMessage{topic: topic, payload: []byte(payload)}
+}

cmd/server/bounded_load_test.go

@@ -0,0 +1,321 @@
+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	_ "modernc.org/sqlite"
+)
+
+// createTestDB creates a temporary SQLite database with N transmissions (1 obs each).
+func createTestDB(t *testing.T, numTx int) string {
+	t.Helper()
+	dir := t.TempDir()
+	dbPath := filepath.Join(dir, "test.db")
+	createTestDBAt(t, dbPath, numTx)
+	return dbPath
+}
+
+// loadStore creates a PacketStore from a test DB with given maxMemoryMB.
+func loadStore(t *testing.T, dbPath string, maxMemMB int) *PacketStore {
+	t.Helper()
+	db, err := OpenDB(dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	cfg := &PacketStoreConfig{MaxMemoryMB: maxMemMB}
+	store := NewPacketStore(db, cfg)
+	if err := store.Load(); err != nil {
+		t.Fatal(err)
+	}
+	return store
+}
+
+func TestBoundedLoad_LimitedMemory(t *testing.T) {
+	dbPath := createTestDB(t, 5000)
+	defer os.RemoveAll(filepath.Dir(dbPath))
+
+	// Use 1MB budget — should load far fewer than 5000 packets
+	store := loadStore(t, dbPath, 1)
+	defer store.db.conn.Close()
+
+	loaded := len(store.packets)
+	if loaded >= 5000 {
+		t.Errorf("expected bounded load to limit packets, got %d/5000", loaded)
+	}
+	if loaded < 1000 {
+		t.Errorf("expected at least 1000 packets (minimum), got %d", loaded)
+	}
+	t.Logf("Loaded %d/5000 packets with 1MB budget", loaded)
+}
+
+func TestBoundedLoad_NewestFirst(t *testing.T) {
+	dbPath := createTestDB(t, 5000)
+	defer os.RemoveAll(filepath.Dir(dbPath))
+
+	store := loadStore(t, dbPath, 1)
+	defer store.db.conn.Close()
+
+	loaded := len(store.packets)
+	if loaded >= 5000 {
+		t.Skip("all packets loaded, can't verify newest-first")
+	}
+
+	// The newest packet in DB has first_seen based on minute 5000.
+	// The loaded packets should be the newest ones.
+	// Last packet in store (sorted ASC) should be the newest in DB.
+	last := store.packets[loaded-1]
+	base := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
+	newestExpected := base.Add(5000 * time.Minute).Format(time.RFC3339)
+	if last.FirstSeen != newestExpected {
+		t.Errorf("expected last packet to be newest (%s), got %s", newestExpected, last.FirstSeen)
+	}
+
+	// First packet should NOT be the oldest in the DB (minute 1)
+	first := store.packets[0]
+	oldestAll := base.Add(1 * time.Minute).Format(time.RFC3339)
+	if first.FirstSeen == oldestAll {
+		t.Errorf("first loaded packet should not be the absolute oldest when bounded")
+	}
+}
+
+func TestBoundedLoad_OldestLoadedSet(t *testing.T) {
+	dbPath := createTestDB(t, 5000)
+	defer os.RemoveAll(filepath.Dir(dbPath))
+
+	store := loadStore(t, dbPath, 1)
+	defer store.db.conn.Close()
+
+	if store.oldestLoaded == "" {
+		t.Fatal("oldestLoaded should be set after bounded load")
+	}
+	if len(store.packets) > 0 && store.oldestLoaded != store.packets[0].FirstSeen {
+		t.Errorf("oldestLoaded (%s) should match first packet (%s)", store.oldestLoaded, store.packets[0].FirstSeen)
+	}
+	t.Logf("oldestLoaded = %s", store.oldestLoaded)
+}
+
+func TestBoundedLoad_UnlimitedWithZero(t *testing.T) {
+	dbPath := createTestDB(t, 200)
+	defer os.RemoveAll(filepath.Dir(dbPath))
+
+	store := loadStore(t, dbPath, 0)
+	defer store.db.conn.Close()
+
+	if len(store.packets) != 200 {
+		t.Errorf("expected all 200 packets with maxMemoryMB=0, got %d", len(store.packets))
+	}
+}
+
+func TestBoundedLoad_AscendingOrder(t *testing.T) {
+	dbPath := createTestDB(t, 3000)
+	defer os.RemoveAll(filepath.Dir(dbPath))
+
+	store := loadStore(t, dbPath, 1)
+	defer store.db.conn.Close()
+
+	// Verify packets are in ascending first_seen order
+	for i := 1; i < len(store.packets); i++ {
+		if store.packets[i].FirstSeen < store.packets[i-1].FirstSeen {
+			t.Fatalf("packets not in ascending order at index %d: %s < %s",
+				i, store.packets[i].FirstSeen, store.packets[i-1].FirstSeen)
+		}
+	}
+}
+
+func TestEstimateStoreTxBytesTypical(t *testing.T) {
+	est := estimateStoreTxBytesTypical(10)
+	if est < 1000 {
+		t.Errorf("typical estimate too low: %d", est)
+	}
+	// Should be roughly proportional to observation count
+	est1 := estimateStoreTxBytesTypical(1)
+	est20 := estimateStoreTxBytesTypical(20)
+	if est20 <= est1 {
+		t.Errorf("estimate should grow with observations: 1obs=%d, 20obs=%d", est1, est20)
+	}
+	t.Logf("Typical estimate: 1obs=%d, 10obs=%d, 20obs=%d bytes", est1, est, est20)
+}
+
+func BenchmarkLoad_Bounded(b *testing.B) {
+	dir := b.TempDir()
+	dbPath := filepath.Join(dir, "bench.db")
+	createTestDBAt(b, dbPath, 5000)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		db, _ := OpenDB(dbPath)
+		cfg := &PacketStoreConfig{MaxMemoryMB: 1}
+		store := NewPacketStore(db, cfg)
+		store.Load()
+		db.conn.Close()
+	}
+}
+
+func BenchmarkLoad_Unlimited(b *testing.B) {
+	dir := b.TempDir()
+	dbPath := filepath.Join(dir, "bench.db")
+	createTestDBAt(b, dbPath, 5000)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		db, _ := OpenDB(dbPath)
+		cfg := &PacketStoreConfig{MaxMemoryMB: 0}
+		store := NewPacketStore(db, cfg)
+		store.Load()
+		db.conn.Close()
+	}
+}
+
+// BenchmarkLoad_30K_Bounded benchmarks bounded Load() with 30K transmissions
+// and realistic observation counts (1–5 per transmission).
+func BenchmarkLoad_30K_Bounded(b *testing.B) {
+	dir := b.TempDir()
+	dbPath := filepath.Join(dir, "bench30k.db")
+	createTestDBWithObs(b, dbPath, 30000)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		db, _ := OpenDB(dbPath)
+		cfg := &PacketStoreConfig{MaxMemoryMB: 50}
+		store := NewPacketStore(db, cfg)
+		store.Load()
+		db.conn.Close()
+	}
+}
+
+// BenchmarkLoad_30K_Unlimited benchmarks unlimited Load() with 30K transmissions
+// and realistic observation counts (1–5 per transmission).
+func BenchmarkLoad_30K_Unlimited(b *testing.B) {
+	dir := b.TempDir()
+	dbPath := filepath.Join(dir, "bench30k.db")
+	createTestDBWithObs(b, dbPath, 30000)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		db, _ := OpenDB(dbPath)
+		cfg := &PacketStoreConfig{MaxMemoryMB: 0}
+		store := NewPacketStore(db, cfg)
+		store.Load()
+		db.conn.Close()
+	}
+}
+
+// createTestDBAt is like createTestDB but writes to a specific path.
+func createTestDBAt(tb testing.TB, dbPath string, numTx int) {
+	tb.Helper()
+	conn, err := sql.Open("sqlite", dbPath+"?_journal_mode=WAL")
+	if err != nil {
+		tb.Fatal(err)
+	}
+	defer conn.Close()
+
+	execOrFail := func(sql string) {
+		if _, err := conn.Exec(sql); err != nil {
+			tb.Fatalf("test DB setup exec failed: %v\nSQL: %s", err, sql)
+		}
+	}
+	execOrFail(`CREATE TABLE IF NOT EXISTS transmissions (
+		id INTEGER PRIMARY KEY,
+		raw_hex TEXT, hash TEXT, first_seen TEXT,
+		route_type INTEGER, payload_type INTEGER,
+		payload_version INTEGER, decoded_json TEXT
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS observations (
+		id INTEGER PRIMARY KEY,
+		transmission_id INTEGER, observer_id TEXT, observer_name TEXT,
+		direction TEXT, snr REAL, rssi REAL, score INTEGER,
+		path_json TEXT, timestamp TEXT
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS observers (rowid INTEGER PRIMARY KEY, id TEXT, name TEXT)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS nodes (
+		pubkey TEXT PRIMARY KEY, name TEXT, role TEXT, lat REAL, lon REAL,
+		last_seen TEXT, first_seen TEXT, frequency REAL
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS schema_version (version INTEGER)`)
+	execOrFail(`INSERT INTO schema_version (version) VALUES (1)`)
+	execOrFail(`CREATE INDEX IF NOT EXISTS idx_tx_first_seen ON transmissions(first_seen)`)
+
+	txStmt, err := conn.Prepare("INSERT INTO transmissions (id, raw_hex, hash, first_seen, route_type, payload_type, payload_version, decoded_json) VALUES (?, ?, ?, ?, ?, ?, ?, ?)")
+	if err != nil {
+		tb.Fatalf("test DB prepare transmissions insert: %v", err)
+	}
+	obsStmt, err := conn.Prepare("INSERT INTO observations (id, transmission_id, observer_id, observer_name, direction, snr, rssi, score, path_json, timestamp) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)")
+	if err != nil {
+		tb.Fatalf("test DB prepare observations insert: %v", err)
+	}
+	defer txStmt.Close()
+	defer obsStmt.Close()
+
+	base := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
+	for i := 1; i <= numTx; i++ {
+		ts := base.Add(time.Duration(i) * time.Minute).Format(time.RFC3339)
+		hash := fmt.Sprintf("h%04d", i)
+		txStmt.Exec(i, "aabb", hash, ts, 0, 4, 1, fmt.Sprintf(`{"pubKey":"pk%04d"}`, i))
+		obsStmt.Exec(i, i, "obs1", "Obs1", "RX", -10.0, -80.0, 5, `["aa","bb"]`, ts)
+	}
+}
+
+// createTestDBWithObs creates a test DB with realistic observation counts (1–5 per tx).
+func createTestDBWithObs(tb testing.TB, dbPath string, numTx int) {
+	tb.Helper()
+	conn, err := sql.Open("sqlite", dbPath+"?_journal_mode=WAL")
+	if err != nil {
+		tb.Fatal(err)
+	}
+	defer conn.Close()
+
+	execOrFail := func(sqlStr string) {
+		if _, err := conn.Exec(sqlStr); err != nil {
+			tb.Fatalf("test DB setup exec failed: %v\nSQL: %s", err, sqlStr)
+		}
+	}
+	execOrFail(`CREATE TABLE IF NOT EXISTS transmissions (
+		id INTEGER PRIMARY KEY, raw_hex TEXT, hash TEXT, first_seen TEXT,
+		route_type INTEGER, payload_type INTEGER, payload_version INTEGER, decoded_json TEXT
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS observations (
+		id INTEGER PRIMARY KEY, transmission_id INTEGER, observer_id TEXT, observer_name TEXT,
+		direction TEXT, snr REAL, rssi REAL, score INTEGER, path_json TEXT, timestamp TEXT
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS observers (rowid INTEGER PRIMARY KEY, id TEXT, name TEXT)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS nodes (
+		pubkey TEXT PRIMARY KEY, name TEXT, role TEXT, lat REAL, lon REAL,
+		last_seen TEXT, first_seen TEXT, frequency REAL
+	)`)
+	execOrFail(`CREATE TABLE IF NOT EXISTS schema_version (version INTEGER)`)
+	execOrFail(`INSERT INTO schema_version (version) VALUES (1)`)
+	execOrFail(`CREATE INDEX IF NOT EXISTS idx_tx_first_seen ON transmissions(first_seen)`)
+
+	txStmt, err := conn.Prepare("INSERT INTO transmissions (id, raw_hex, hash, first_seen, route_type, payload_type, payload_version, decoded_json) VALUES (?, ?, ?, ?, ?, ?, ?, ?)")
+	if err != nil {
+		tb.Fatalf("test DB prepare transmissions: %v", err)
+	}
+	obsStmt, err := conn.Prepare("INSERT INTO observations (id, transmission_id, observer_id, observer_name, direction, snr, rssi, score, path_json, timestamp) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)")
+	if err != nil {
+		tb.Fatalf("test DB prepare observations: %v", err)
+	}
+	defer txStmt.Close()
+	defer obsStmt.Close()
+
+	observers := []string{"obs1", "obs2", "obs3", "obs4", "obs5"}
+	obsNames := []string{"Alpha", "Bravo", "Charlie", "Delta", "Echo"}
+	obsID := 1
+	base := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
+	for i := 1; i <= numTx; i++ {
+		ts := base.Add(time.Duration(i) * time.Minute).Format(time.RFC3339)
+		hash := fmt.Sprintf("h%06d", i)
+		txStmt.Exec(i, "aabb", hash, ts, 0, 4, 1, fmt.Sprintf(`{"pubKey":"pk%06d"}`, i))
+		nObs := (i % 5) + 1 // 1–5 observations per transmission
+		for j := 0; j < nObs; j++ {
+			snr := -5.0 + float64(j)*2.5
+			rssi := -90.0 + float64(j)*5.0
+			obsStmt.Exec(obsID, i, observers[j], obsNames[j], "RX", snr, rssi, 5-j, `["aa","bb"]`, ts)
+			obsID++
+		}
+	}
+}

cmd/server/channel_filter_test.go

@@ -0,0 +1,57 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+)
+
+// TestPacketsChannelFilter verifies /api/packets?channel=... actually filters
+// (regression test for #812).
+func TestPacketsChannelFilter(t *testing.T) {
+	_, router := setupTestServer(t)
+
+	get := func(url string) map[string]interface{} {
+		req := httptest.NewRequest("GET", url, nil)
+		w := httptest.NewRecorder()
+		router.ServeHTTP(w, req)
+		if w.Code != http.StatusOK {
+			t.Fatalf("GET %s: expected 200, got %d", url, w.Code)
+		}
+		var body map[string]interface{}
+		if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
+			t.Fatalf("decode %s: %v", url, err)
+		}
+		return body
+	}
+
+	all := get("/api/packets?limit=50")
+	allTotal := int(all["total"].(float64))
+	if allTotal < 2 {
+		t.Fatalf("expected baseline >= 2 packets, got %d", allTotal)
+	}
+
+	test := get("/api/packets?limit=50&channel=%23test")
+	testTotal := int(test["total"].(float64))
+	if testTotal == 0 {
+		t.Fatalf("channel=#test: expected >= 1 match, got 0 (filter ignored?)")
+	}
+	if testTotal >= allTotal {
+		t.Fatalf("channel=#test: expected fewer packets than baseline (%d), got %d", allTotal, testTotal)
+	}
+
+	// Every returned packet must be a CHAN/GRP_TXT (payload_type=5) on #test.
+	pkts, _ := test["packets"].([]interface{})
+	for _, p := range pkts {
+		m := p.(map[string]interface{})
+		if pt, _ := m["payload_type"].(float64); int(pt) != 5 {
+			t.Errorf("channel=#test: returned non-GRP_TXT packet (payload_type=%v)", m["payload_type"])
+		}
+	}
+
+	none := get("/api/packets?limit=50&channel=nonexistentchannel")
+	if int(none["total"].(float64)) != 0 {
+		t.Fatalf("channel=nonexistentchannel: expected total=0, got %v", none["total"])
+	}
+}

cmd/server/clock_skew.go

@@ -0,0 +1,748 @@
+package main
+
+import (
+	"math"
+	"sort"
+	"sync"
+	"time"
+)
+
+// ── Clock Skew Severity ────────────────────────────────────────────────────────
+
+type SkewSeverity string
+
+const (
+	SkewOK       SkewSeverity = "ok"       // < 5 min
+	SkewWarning  SkewSeverity = "warning"  // 5 min – 1 hour
+	SkewCritical SkewSeverity = "critical" // 1 hour – 30 days
+	SkewAbsurd   SkewSeverity = "absurd"   // > 30 days
+	SkewNoClock      SkewSeverity = "no_clock"      // > 365 days — uninitialized RTC
+	SkewBimodalClock SkewSeverity = "bimodal_clock" // mixed good+bad recent samples (flaky RTC)
+)
+
+// Default thresholds in seconds.
+const (
+	skewThresholdWarnSec     = 5 * 60          // 5 minutes
+	skewThresholdCriticalSec = 60 * 60         // 1 hour
+	skewThresholdAbsurdSec   = 30 * 24 * 3600  // 30 days
+	skewThresholdNoClockSec  = 365 * 24 * 3600 // 365 days — uninitialized RTC
+
+	// minDriftSamples is the minimum number of advert transmissions needed
+	// to compute a meaningful linear drift rate.
+	minDriftSamples = 5
+
+	// maxReasonableDriftPerDay caps drift display. Physically impossible
+	// drift rates (> 1 day/day) indicate insufficient or outlier samples.
+	maxReasonableDriftPerDay = 86400.0
+
+	// recentSkewWindowCount is the number of most-recent advert samples
+	// used to derive the "current" skew for severity classification (see
+	// issue #789). The all-time median is poisoned by historical bad
+	// samples (e.g. a node that was off and then GPS-corrected); severity
+	// must reflect current health, not lifetime statistics.
+	recentSkewWindowCount = 5
+
+	// recentSkewWindowSec bounds the recent-window in time as well: only
+	// samples from the last N seconds count as "recent" for severity.
+	// The effective window is min(recentSkewWindowCount, samples in 1h).
+	recentSkewWindowSec = 3600
+
+	// bimodalSkewThresholdSec is the absolute skew threshold (1 hour)
+	// above which a sample is considered "bad" — likely firmware emitting
+	// a nonsense timestamp from an uninitialized RTC, not real drift.
+	// Chosen to match the warning/critical severity boundary: real clock
+	// drift rarely exceeds 1 hour, while epoch-0 RTCs produce ~1.7B sec.
+	bimodalSkewThresholdSec = 3600.0
+
+	// maxPlausibleSkewJumpSec is the largest skew change between
+	// consecutive samples that we treat as physical drift. Anything larger
+	// (e.g. a GPS sync that jumps the clock by minutes/days) is rejected
+	// as an outlier when computing drift. Real microcontroller drift is
+	// fractions of a second per advert; 60s is a generous safety factor.
+	maxPlausibleSkewJumpSec = 60.0
+
+	// theilSenMaxPoints caps the number of points fed to Theil-Sen
+	// regression (O(n²) in pairs). For nodes with thousands of samples we
+	// keep the most-recent points, which are also the most relevant for
+	// current drift.
+	theilSenMaxPoints = 200
+)
+
+// classifySkew maps absolute skew (seconds) to a severity level.
+// Float64 comparison is safe: inputs are rounded to 1 decimal via round(),
+// and thresholds are integer multiples of 60 — no rounding artifacts.
+func classifySkew(absSkewSec float64) SkewSeverity {
+	switch {
+	case absSkewSec >= skewThresholdNoClockSec:
+		return SkewNoClock
+	case absSkewSec >= skewThresholdAbsurdSec:
+		return SkewAbsurd
+	case absSkewSec >= skewThresholdCriticalSec:
+		return SkewCritical
+	case absSkewSec >= skewThresholdWarnSec:
+		return SkewWarning
+	default:
+		return SkewOK
+	}
+}
+
+// ── Data Types ─────────────────────────────────────────────────────────────────
+
+// skewSample is a single raw skew measurement from one advert observation.
+type skewSample struct {
+	advertTS    int64  // node's advert Unix timestamp
+	observedTS  int64  // observation Unix timestamp
+	observerID  string // which observer saw this
+	hash        string // transmission hash (for multi-observer grouping)
+}
+
+// ObserverCalibration holds the computed clock offset for an observer.
+type ObserverCalibration struct {
+	ObserverID string  `json:"observerID"`
+	OffsetSec  float64 `json:"offsetSec"`  // positive = observer clock ahead
+	Samples    int     `json:"samples"`    // number of multi-observer packets used
+}
+
+// NodeClockSkew is the API response for a single node's clock skew data.
+type NodeClockSkew struct {
+	Pubkey          string       `json:"pubkey"`
+	MeanSkewSec     float64      `json:"meanSkewSec"`     // corrected mean skew (positive = node ahead)
+	MedianSkewSec   float64      `json:"medianSkewSec"`   // corrected median skew
+	LastSkewSec     float64      `json:"lastSkewSec"`     // most recent corrected skew
+	RecentMedianSkewSec float64  `json:"recentMedianSkewSec"` // median across most-recent samples (drives severity, see #789)
+	DriftPerDaySec  float64      `json:"driftPerDaySec"`  // linear drift rate (sec/day)
+	Severity        SkewSeverity `json:"severity"`
+	SampleCount     int          `json:"sampleCount"`
+	Calibrated      bool         `json:"calibrated"`      // true if observer calibration was applied
+	LastAdvertTS    int64        `json:"lastAdvertTS"`     // most recent advert timestamp
+	LastObservedTS  int64        `json:"lastObservedTS"`   // most recent observation timestamp
+	Samples         []SkewSample `json:"samples,omitempty"` // time-series for sparklines
+	GoodFraction        float64  `json:"goodFraction"`        // fraction of recent samples with |skew| <= 1h
+	RecentBadSampleCount int     `json:"recentBadSampleCount"` // count of recent samples with |skew| > 1h
+	RecentSampleCount    int     `json:"recentSampleCount"`    // total recent samples in window
+	NodeName        string       `json:"nodeName,omitempty"` // populated in fleet responses
+	NodeRole        string       `json:"nodeRole,omitempty"` // populated in fleet responses
+}
+
+// SkewSample is a single (timestamp, skew) point for sparkline rendering.
+type SkewSample struct {
+	Timestamp int64   `json:"ts"`   // Unix epoch of observation
+	SkewSec   float64 `json:"skew"` // corrected skew in seconds
+}
+
+// txSkewResult maps tx hash → per-transmission skew stats. This is an
+// intermediate result keyed by hash (not pubkey); the store maps hash → pubkey
+// when building the final per-node view.
+type txSkewResult = map[string]*NodeClockSkew
+
+// ── Clock Skew Engine ──────────────────────────────────────────────────────────
+
+// ClockSkewEngine computes and caches clock skew data for nodes and observers.
+type ClockSkewEngine struct {
+	mu               sync.RWMutex
+	observerOffsets  map[string]float64 // observerID → calibrated offset (seconds)
+	observerSamples  map[string]int     // observerID → number of multi-observer packets used
+	nodeSkew         txSkewResult
+	lastComputed     time.Time
+	computeInterval  time.Duration
+}
+
+func NewClockSkewEngine() *ClockSkewEngine {
+	return &ClockSkewEngine{
+		observerOffsets:  make(map[string]float64),
+		observerSamples: make(map[string]int),
+		nodeSkew:       make(txSkewResult),
+		computeInterval: 30 * time.Second,
+	}
+}
+
+// Recompute recalculates all clock skew data from the packet store.
+// Called periodically or on demand. Holds store RLock externally.
+// Uses read-copy-update: heavy computation runs outside the write lock,
+// then results are swapped in under a brief lock.
+func (e *ClockSkewEngine) Recompute(store *PacketStore) {
+	// Fast path: check under read lock if recompute is needed.
+	e.mu.RLock()
+	fresh := time.Since(e.lastComputed) < e.computeInterval
+	e.mu.RUnlock()
+	if fresh {
+		return
+	}
+
+	// Phase 1: Collect skew samples from ADVERT packets (store RLock held by caller).
+	samples := collectSamples(store)
+
+	// Phase 2–3: Compute outside the write lock.
+	var newOffsets map[string]float64
+	var newSamples map[string]int
+	var newNodeSkew txSkewResult
+
+	if len(samples) > 0 {
+		newOffsets, newSamples = calibrateObservers(samples)
+		newNodeSkew = computeNodeSkew(samples, newOffsets)
+	} else {
+		newOffsets = make(map[string]float64)
+		newSamples = make(map[string]int)
+		newNodeSkew = make(txSkewResult)
+	}
+
+	// Swap results under brief write lock.
+	e.mu.Lock()
+	// Re-check: another goroutine may have computed while we were working.
+	if time.Since(e.lastComputed) < e.computeInterval {
+		e.mu.Unlock()
+		return
+	}
+	e.observerOffsets = newOffsets
+	e.observerSamples = newSamples
+	e.nodeSkew = newNodeSkew
+	e.lastComputed = time.Now()
+	e.mu.Unlock()
+}
+
+// collectSamples extracts skew samples from ADVERT packets in the store.
+// Must be called with store.mu held (at least RLock).
+func collectSamples(store *PacketStore) []skewSample {
+	adverts := store.byPayloadType[PayloadADVERT]
+	if len(adverts) == 0 {
+		return nil
+	}
+
+	samples := make([]skewSample, 0, len(adverts)*2)
+	for _, tx := range adverts {
+		decoded := tx.ParsedDecoded()
+		if decoded == nil {
+			continue
+		}
+		// Extract advert timestamp from decoded JSON.
+		advertTS := extractTimestamp(decoded)
+		if advertTS <= 0 {
+			continue
+		}
+		// Sanity: skip timestamps before year 2020 or after year 2100.
+		if advertTS < 1577836800 || advertTS > 4102444800 {
+			continue
+		}
+
+		for _, obs := range tx.Observations {
+			obsTS := parseISO(obs.Timestamp)
+			if obsTS <= 0 {
+				continue
+			}
+			samples = append(samples, skewSample{
+				advertTS:   advertTS,
+				observedTS: obsTS,
+				observerID: obs.ObserverID,
+				hash:       tx.Hash,
+			})
+		}
+	}
+	return samples
+}
+
+// extractTimestamp gets the Unix timestamp from a decoded ADVERT payload.
+func extractTimestamp(decoded map[string]interface{}) int64 {
+	// Try payload.timestamp first (nested in "payload" key).
+	if payload, ok := decoded["payload"]; ok {
+		if pm, ok := payload.(map[string]interface{}); ok {
+			if ts := jsonNumber(pm, "timestamp"); ts > 0 {
+				return ts
+			}
+		}
+	}
+	// Fallback: top-level timestamp.
+	if ts := jsonNumber(decoded, "timestamp"); ts > 0 {
+		return ts
+	}
+	return 0
+}
+
+// jsonNumber extracts an int64 from a JSON-parsed map (handles float64 and json.Number).
+func jsonNumber(m map[string]interface{}, key string) int64 {
+	v, ok := m[key]
+	if !ok || v == nil {
+		return 0
+	}
+	switch n := v.(type) {
+	case float64:
+		return int64(n)
+	case int64:
+		return n
+	case int:
+		return int64(n)
+	}
+	return 0
+}
+
+// parseISO parses an ISO 8601 timestamp string to Unix seconds.
+func parseISO(s string) int64 {
+	if s == "" {
+		return 0
+	}
+	t, err := time.Parse(time.RFC3339, s)
+	if err != nil {
+		// Try with fractional seconds.
+		t, err = time.Parse("2006-01-02T15:04:05.999999999Z07:00", s)
+		if err != nil {
+			return 0
+		}
+	}
+	return t.Unix()
+}
+
+// ── Phase 2: Observer Calibration ──────────────────────────────────────────────
+
+// calibrateObservers computes each observer's clock offset using multi-observer
+// packets. Returns offset map and sample count map.
+func calibrateObservers(samples []skewSample) (map[string]float64, map[string]int) {
+	// Group observations by packet hash.
+	byHash := make(map[string][]skewSample)
+	for _, s := range samples {
+		byHash[s.hash] = append(byHash[s.hash], s)
+	}
+
+	// For each multi-observer packet, compute per-observer deviation from median.
+	deviations := make(map[string][]float64) // observerID → list of deviations
+	for _, group := range byHash {
+		if len(group) < 2 {
+			continue // single-observer packet, can't calibrate
+		}
+		// Compute median observation timestamp for this packet.
+		obsTimes := make([]float64, len(group))
+		for i, s := range group {
+			obsTimes[i] = float64(s.observedTS)
+		}
+		medianObs := median(obsTimes)
+		for _, s := range group {
+			dev := float64(s.observedTS) - medianObs
+			deviations[s.observerID] = append(deviations[s.observerID], dev)
+		}
+	}
+
+	// Each observer's offset = median of its deviations.
+	offsets := make(map[string]float64, len(deviations))
+	counts := make(map[string]int, len(deviations))
+	for obsID, devs := range deviations {
+		offsets[obsID] = median(devs)
+		counts[obsID] = len(devs)
+	}
+	return offsets, counts
+}
+
+// ── Phase 3: Per-Node Skew ─────────────────────────────────────────────────────
+
+// computeNodeSkew calculates corrected skew statistics for each node.
+func computeNodeSkew(samples []skewSample, obsOffsets map[string]float64) txSkewResult {
+	// Compute corrected skew per sample, grouped by hash (each hash = one
+	// node's advert transmission). The caller maps hash → pubkey via byNode.
+	type correctedSample struct {
+		skew       float64
+		observedTS int64
+		calibrated bool
+	}
+
+	byHash := make(map[string][]correctedSample)
+	hashAdvertTS := make(map[string]int64)
+
+	for _, s := range samples {
+		obsOffset, hasCal := obsOffsets[s.observerID]
+		rawSkew := float64(s.advertTS - s.observedTS)
+		corrected := rawSkew
+		if hasCal {
+			// Observer offset = obs_ts - median(all_obs_ts). If observer is ahead,
+			// its obs_ts is inflated, making raw_skew too low. Add offset to correct.
+			corrected = rawSkew + obsOffset
+		}
+		byHash[s.hash] = append(byHash[s.hash], correctedSample{
+			skew:       corrected,
+			observedTS: s.observedTS,
+			calibrated: hasCal,
+		})
+		hashAdvertTS[s.hash] = s.advertTS
+	}
+
+	// Each hash represents one advert from one node. Compute median corrected
+	// skew per hash (across multiple observers).
+
+	result := make(map[string]*NodeClockSkew) // keyed by hash for now
+	for hash, cs := range byHash {
+		skews := make([]float64, len(cs))
+		for i, c := range cs {
+			skews[i] = c.skew
+		}
+		medSkew := median(skews)
+		meanSkew := mean(skews)
+
+		// Find latest observation.
+		var latestObsTS int64
+		var anyCal bool
+		for _, c := range cs {
+			if c.observedTS > latestObsTS {
+				latestObsTS = c.observedTS
+			}
+			if c.calibrated {
+				anyCal = true
+			}
+		}
+
+		absMedian := math.Abs(medSkew)
+		result[hash] = &NodeClockSkew{
+			MeanSkewSec:    round(meanSkew, 1),
+			MedianSkewSec:  round(medSkew, 1),
+			LastSkewSec:    round(cs[len(cs)-1].skew, 1),
+			Severity:       classifySkew(absMedian),
+			SampleCount:    len(cs),
+			Calibrated:     anyCal,
+			LastAdvertTS:   hashAdvertTS[hash],
+			LastObservedTS: latestObsTS,
+		}
+	}
+	return result
+}
+
+// ── Integration with PacketStore ───────────────────────────────────────────────
+
+// GetNodeClockSkew returns the clock skew data for a specific node (acquires RLock).
+func (s *PacketStore) GetNodeClockSkew(pubkey string) *NodeClockSkew {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return s.getNodeClockSkewLocked(pubkey)
+}
+
+// getNodeClockSkewLocked returns clock skew for a node.
+// Must be called with s.mu held (at least RLock).
+func (s *PacketStore) getNodeClockSkewLocked(pubkey string) *NodeClockSkew {
+	s.clockSkew.Recompute(s)
+
+	txs := s.byNode[pubkey]
+	if len(txs) == 0 {
+		return nil
+	}
+
+	s.clockSkew.mu.RLock()
+	defer s.clockSkew.mu.RUnlock()
+
+	var allSkews []float64
+	var lastSkew float64
+	var lastObsTS, lastAdvTS int64
+	var totalSamples int
+	var anyCal bool
+	var tsSkews []tsSkewPair
+
+	for _, tx := range txs {
+		if tx.PayloadType == nil || *tx.PayloadType != PayloadADVERT {
+			continue
+		}
+		cs, ok := s.clockSkew.nodeSkew[tx.Hash]
+		if !ok {
+			continue
+		}
+		allSkews = append(allSkews, cs.MedianSkewSec)
+		totalSamples += cs.SampleCount
+		if cs.Calibrated {
+			anyCal = true
+		}
+		if cs.LastObservedTS > lastObsTS {
+			lastObsTS = cs.LastObservedTS
+			lastSkew = cs.LastSkewSec
+			lastAdvTS = cs.LastAdvertTS
+		}
+		tsSkews = append(tsSkews, tsSkewPair{ts: cs.LastObservedTS, skew: cs.MedianSkewSec})
+	}
+
+	if len(allSkews) == 0 {
+		return nil
+	}
+
+	medSkew := median(allSkews)
+	meanSkew := mean(allSkews)
+
+	// Severity is derived from RECENT samples only (issue #789). The
+	// all-time median is poisoned by historical bad data — a node that
+	// was off for hours and then GPS-corrected can have median = -59M sec
+	// while its current skew is -0.8s. Operators need severity to reflect
+	// current health, so they trust the dashboard.
+	//
+	// Sort tsSkews by time and take the last recentSkewWindowCount samples
+	// (or all samples within recentSkewWindowSec of the latest, whichever
+	// gives FEWER samples — we want the more-current view; a chatty node
+	// can fit dozens of samples in 1h, in which case the count cap wins).
+	sort.Slice(tsSkews, func(i, j int) bool { return tsSkews[i].ts < tsSkews[j].ts })
+
+	recentSkew := lastSkew
+	var recentVals []float64
+	if n := len(tsSkews); n > 0 {
+		latestTS := tsSkews[n-1].ts
+		// Index-based window: last K samples.
+		startByCount := n - recentSkewWindowCount
+		if startByCount < 0 {
+			startByCount = 0
+		}
+		// Time-based window: samples newer than latestTS - windowSec.
+		startByTime := n - 1
+		for i := n - 1; i >= 0; i-- {
+			if latestTS-tsSkews[i].ts <= recentSkewWindowSec {
+				startByTime = i
+			} else {
+				break
+			}
+		}
+		// Pick the narrower (larger-index) of the two windows — the most
+		// current view of the node's clock health.
+		start := startByCount
+		if startByTime > start {
+			start = startByTime
+		}
+		recentVals = make([]float64, 0, n-start)
+		for i := start; i < n; i++ {
+			recentVals = append(recentVals, tsSkews[i].skew)
+		}
+		if len(recentVals) > 0 {
+			recentSkew = median(recentVals)
+		}
+	}
+
+	// ── Bimodal detection (#845) ─────────────────────────────────────────
+	// Split recent samples into "good" (|skew| <= 1h, real clock) and
+	// "bad" (|skew| > 1h, firmware nonsense from uninitialized RTC).
+	// Classification order (first match wins):
+	//   no_clock       — goodFraction < 0.10 (essentially no real clock)
+	//   bimodal_clock  — 0.10 <= goodFraction < 0.80 AND badCount > 0
+	//   ok/warn/etc.   — goodFraction >= 0.80 (normal, outliers filtered)
+	var goodSamples []float64
+	for _, v := range recentVals {
+		if math.Abs(v) <= bimodalSkewThresholdSec {
+			goodSamples = append(goodSamples, v)
+		}
+	}
+	recentSampleCount := len(recentVals)
+	recentBadCount := recentSampleCount - len(goodSamples)
+	var goodFraction float64
+	if recentSampleCount > 0 {
+		goodFraction = float64(len(goodSamples)) / float64(recentSampleCount)
+	}
+
+	var severity SkewSeverity
+	if goodFraction < 0.10 {
+		// Essentially no real clock — classify as no_clock regardless
+		// of the raw skew magnitude.
+		severity = SkewNoClock
+	} else if goodFraction < 0.80 && recentBadCount > 0 {
+		// Bimodal: use median of GOOD samples as the "real" skew.
+		severity = SkewBimodalClock
+		if len(goodSamples) > 0 {
+			recentSkew = median(goodSamples)
+		}
+	} else {
+		// Normal path: if there are good samples, use their median
+		// (filters out rare outliers in ≥80% good case).
+		if len(goodSamples) > 0 && recentBadCount > 0 {
+			recentSkew = median(goodSamples)
+		}
+		severity = classifySkew(math.Abs(recentSkew))
+	}
+
+	// For no_clock / bimodal_clock nodes, skip drift when data is unreliable.
+	var drift float64
+	if severity != SkewNoClock && severity != SkewBimodalClock && len(tsSkews) >= minDriftSamples {
+		drift = computeDrift(tsSkews)
+		// Cap physically impossible drift rates.
+		if math.Abs(drift) > maxReasonableDriftPerDay {
+			drift = 0
+		}
+	}
+
+	// Build sparkline samples from tsSkews (already sorted by time above).
+	samples := make([]SkewSample, len(tsSkews))
+	for i, p := range tsSkews {
+		samples[i] = SkewSample{Timestamp: p.ts, SkewSec: round(p.skew, 1)}
+	}
+
+	return &NodeClockSkew{
+		Pubkey:               pubkey,
+		MeanSkewSec:          round(meanSkew, 1),
+		MedianSkewSec:        round(medSkew, 1),
+		LastSkewSec:          round(lastSkew, 1),
+		RecentMedianSkewSec:  round(recentSkew, 1),
+		DriftPerDaySec:       round(drift, 2),
+		Severity:             severity,
+		SampleCount:          totalSamples,
+		Calibrated:           anyCal,
+		LastAdvertTS:         lastAdvTS,
+		LastObservedTS:       lastObsTS,
+		Samples:              samples,
+		GoodFraction:         round(goodFraction, 2),
+		RecentBadSampleCount: recentBadCount,
+		RecentSampleCount:    recentSampleCount,
+	}
+}
+
+// GetFleetClockSkew returns clock skew data for all nodes that have skew data.
+// Must NOT be called with s.mu held.
+func (s *PacketStore) GetFleetClockSkew() []*NodeClockSkew {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	// Build name/role lookup from DB cache (requires s.mu held).
+	allNodes, _ := s.getCachedNodesAndPM()
+	nameMap := make(map[string]nodeInfo, len(allNodes))
+	for _, ni := range allNodes {
+		nameMap[ni.PublicKey] = ni
+	}
+
+	var results []*NodeClockSkew
+	for pubkey := range s.byNode {
+		cs := s.getNodeClockSkewLocked(pubkey)
+		if cs == nil {
+			continue
+		}
+		// Enrich with node name/role.
+		if ni, ok := nameMap[pubkey]; ok {
+			cs.NodeName = ni.Name
+			cs.NodeRole = ni.Role
+		}
+		// Omit samples in fleet response (too much data).
+		cs.Samples = nil
+		results = append(results, cs)
+	}
+	return results
+}
+
+// GetObserverCalibrations returns the current observer clock offsets.
+func (s *PacketStore) GetObserverCalibrations() []ObserverCalibration {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+
+	s.clockSkew.Recompute(s)
+
+	s.clockSkew.mu.RLock()
+	defer s.clockSkew.mu.RUnlock()
+
+	result := make([]ObserverCalibration, 0, len(s.clockSkew.observerOffsets))
+	for obsID, offset := range s.clockSkew.observerOffsets {
+		result = append(result, ObserverCalibration{
+			ObserverID: obsID,
+			OffsetSec:  round(offset, 1),
+			Samples:    s.clockSkew.observerSamples[obsID],
+		})
+	}
+	// Sort by absolute offset descending.
+	sort.Slice(result, func(i, j int) bool {
+		return math.Abs(result[i].OffsetSec) > math.Abs(result[j].OffsetSec)
+	})
+	return result
+}
+
+// ── Math Helpers ───────────────────────────────────────────────────────────────
+
+func median(vals []float64) float64 {
+	if len(vals) == 0 {
+		return 0
+	}
+	sorted := make([]float64, len(vals))
+	copy(sorted, vals)
+	sort.Float64s(sorted)
+	n := len(sorted)
+	if n%2 == 0 {
+		return (sorted[n/2-1] + sorted[n/2]) / 2
+	}
+	return sorted[n/2]
+}
+
+func mean(vals []float64) float64 {
+	if len(vals) == 0 {
+		return 0
+	}
+	sum := 0.0
+	for _, v := range vals {
+		sum += v
+	}
+	return sum / float64(len(vals))
+}
+
+// tsSkewPair is a (timestamp, skew) pair for drift estimation.
+type tsSkewPair struct {
+	ts   int64
+	skew float64
+}
+
+// computeDrift estimates linear drift in seconds per day from time-ordered
+// (timestamp, skew) pairs. Issue #789: a single GPS-correction event (huge
+// skew jump in seconds) used to dominate ordinary least squares and produce
+// absurd drift like 1.7M sec/day. We now:
+//
+//  1. Drop pairs whose consecutive skew jump exceeds maxPlausibleSkewJumpSec
+//     (clock corrections, not physical drift). This protects both OLS-style
+//     consumers and Theil-Sen.
+//  2. Use Theil-Sen regression — the slope is the median of all pairwise
+//     slopes, naturally robust to remaining outliers (breakdown point ~29%).
+//
+// For very small samples after filtering we fall back to a simple slope
+// between first and last calibrated samples.
+func computeDrift(pairs []tsSkewPair) float64 {
+	if len(pairs) < 2 {
+		return 0
+	}
+	// Sort by timestamp.
+	sort.Slice(pairs, func(i, j int) bool {
+		return pairs[i].ts < pairs[j].ts
+	})
+
+	// Time span too short? Skip.
+	spanSec := float64(pairs[len(pairs)-1].ts - pairs[0].ts)
+	if spanSec < 3600 { // need at least 1 hour of data
+		return 0
+	}
+
+	// Outlier filter: drop samples where the skew jumps more than
+	// maxPlausibleSkewJumpSec from the running "stable" baseline.
+	// We anchor on the first sample, then accept each subsequent point
+	// that's within the threshold of the most recent accepted point —
+	// this preserves a slow drift while rejecting correction events.
+	filtered := make([]tsSkewPair, 0, len(pairs))
+	filtered = append(filtered, pairs[0])
+	for i := 1; i < len(pairs); i++ {
+		prev := filtered[len(filtered)-1]
+		if math.Abs(pairs[i].skew-prev.skew) <= maxPlausibleSkewJumpSec {
+			filtered = append(filtered, pairs[i])
+		}
+	}
+	// If the filter killed too much (e.g. unstable node), fall back to the
+	// raw series so we at least produce *something* — it'll be capped by
+	// maxReasonableDriftPerDay downstream.
+	if len(filtered) < 2 || float64(filtered[len(filtered)-1].ts-filtered[0].ts) < 3600 {
+		filtered = pairs
+	}
+
+	// Cap point count for Theil-Sen (O(n²) on pairs). Keep most-recent.
+	if len(filtered) > theilSenMaxPoints {
+		filtered = filtered[len(filtered)-theilSenMaxPoints:]
+	}
+
+	return theilSenSlope(filtered) * 86400 // sec/sec → sec/day
+}
+
+// theilSenSlope returns the Theil-Sen estimator: median of all pairwise
+// slopes (yj - yi) / (tj - ti) for i < j. Naturally robust to outliers.
+// Pairs must be sorted by timestamp ascending.
+func theilSenSlope(pairs []tsSkewPair) float64 {
+	n := len(pairs)
+	if n < 2 {
+		return 0
+	}
+	// Pre-allocate: n*(n-1)/2 pairs.
+	slopes := make([]float64, 0, n*(n-1)/2)
+	for i := 0; i < n; i++ {
+		for j := i + 1; j < n; j++ {
+			dt := float64(pairs[j].ts - pairs[i].ts)
+			if dt <= 0 {
+				continue
+			}
+			slopes = append(slopes, (pairs[j].skew-pairs[i].skew)/dt)
+		}
+	}
+	if len(slopes) == 0 {
+		return 0
+	}
+	return median(slopes)
+}

cmd/server/clock_skew_test.go

@@ -0,0 +1,956 @@
+package main
+
+import (
+	"fmt"
+	"math"
+	"testing"
+	"time"
+)
+
+// ── classifySkew ───────────────────────────────────────────────────────────────
+
+func TestClassifySkew(t *testing.T) {
+	tests := []struct {
+		absSkew  float64
+		expected SkewSeverity
+	}{
+		{0, SkewOK},
+		{60, SkewOK},           // 1 min
+		{299, SkewOK},          // just under 5 min
+		{300, SkewWarning},     // exactly 5 min
+		{1800, SkewWarning},    // 30 min
+		{3599, SkewWarning},    // just under 1 hour
+		{3600, SkewCritical},   // exactly 1 hour
+		{86400, SkewCritical},  // 1 day
+		{2592000 - 1, SkewCritical}, // just under 30 days
+		{2592000, SkewAbsurd},  // exactly 30 days
+		{86400 * 365 - 1, SkewAbsurd}, // just under 365 days
+		{86400 * 365, SkewNoClock}, // exactly 365 days
+		{86400 * 365 * 10, SkewNoClock}, // 10 years (epoch-0 style)
+	}
+	for _, tc := range tests {
+		got := classifySkew(tc.absSkew)
+		if got != tc.expected {
+			t.Errorf("classifySkew(%v) = %v, want %v", tc.absSkew, got, tc.expected)
+		}
+	}
+}
+
+// ── median ─────────────────────────────────────────────────────────────────────
+
+func TestMedian(t *testing.T) {
+	tests := []struct {
+		vals     []float64
+		expected float64
+	}{
+		{nil, 0},
+		{[]float64{}, 0},
+		{[]float64{5}, 5},
+		{[]float64{1, 3}, 2},
+		{[]float64{3, 1, 2}, 2},
+		{[]float64{4, 1, 3, 2}, 2.5},
+		{[]float64{-10, 0, 10}, 0},
+	}
+	for _, tc := range tests {
+		got := median(tc.vals)
+		if got != tc.expected {
+			t.Errorf("median(%v) = %v, want %v", tc.vals, got, tc.expected)
+		}
+	}
+}
+
+func TestMean(t *testing.T) {
+	tests := []struct {
+		vals     []float64
+		expected float64
+	}{
+		{nil, 0},
+		{[]float64{10}, 10},
+		{[]float64{2, 4, 6}, 4},
+	}
+	for _, tc := range tests {
+		got := mean(tc.vals)
+		if got != tc.expected {
+			t.Errorf("mean(%v) = %v, want %v", tc.vals, got, tc.expected)
+		}
+	}
+}
+
+// ── parseISO ───────────────────────────────────────────────────────────────────
+
+func TestParseISO(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected int64
+	}{
+		{"", 0},
+		{"garbage", 0},
+		{"2026-04-15T12:00:00Z", 1776254400},
+		{"2026-04-15T12:00:00+00:00", 1776254400},
+	}
+	for _, tc := range tests {
+		got := parseISO(tc.input)
+		if got != tc.expected {
+			t.Errorf("parseISO(%q) = %v, want %v", tc.input, got, tc.expected)
+		}
+	}
+}
+
+// ── extractTimestamp ────────────────────────────────────────────────────────────
+
+func TestExtractTimestamp(t *testing.T) {
+	// Nested payload.timestamp
+	decoded := map[string]interface{}{
+		"payload": map[string]interface{}{
+			"timestamp": float64(1776340800),
+		},
+	}
+	got := extractTimestamp(decoded)
+	if got != 1776340800 {
+		t.Errorf("extractTimestamp (nested) = %v, want 1776340800", got)
+	}
+
+	// Top-level timestamp
+	decoded2 := map[string]interface{}{
+		"timestamp": float64(1776340900),
+	}
+	got2 := extractTimestamp(decoded2)
+	if got2 != 1776340900 {
+		t.Errorf("extractTimestamp (top-level) = %v, want 1776340900", got2)
+	}
+
+	// No timestamp
+	decoded3 := map[string]interface{}{"foo": "bar"}
+	got3 := extractTimestamp(decoded3)
+	if got3 != 0 {
+		t.Errorf("extractTimestamp (missing) = %v, want 0", got3)
+	}
+}
+
+// ── calibrateObservers ─────────────────────────────────────────────────────────
+
+func TestCalibrateObservers_SingleObserver(t *testing.T) {
+	// Single-observer packets can't calibrate — should return empty.
+	samples := []skewSample{
+		{advertTS: 1000, observedTS: 1000, observerID: "obs1", hash: "h1"},
+		{advertTS: 2000, observedTS: 2000, observerID: "obs1", hash: "h2"},
+	}
+	offsets, _ := calibrateObservers(samples)
+	if len(offsets) != 0 {
+		t.Errorf("expected no offsets for single-observer, got %v", offsets)
+	}
+}
+
+func TestCalibrateObservers_MultiObserver(t *testing.T) {
+	// Packet h1 seen by 3 observers: obs1 at t=100, obs2 at t=110, obs3 at t=100.
+	// Median observation = 100. obs1=0, obs2=+10, obs3=0
+	// Packet h2 seen by 3 observers: obs1 at t=200, obs2 at t=210, obs3 at t=200.
+	// Median observation = 200. obs1=0, obs2=+10, obs3=0
+	samples := []skewSample{
+		{advertTS: 100, observedTS: 100, observerID: "obs1", hash: "h1"},
+		{advertTS: 100, observedTS: 110, observerID: "obs2", hash: "h1"},
+		{advertTS: 100, observedTS: 100, observerID: "obs3", hash: "h1"},
+		{advertTS: 200, observedTS: 200, observerID: "obs1", hash: "h2"},
+		{advertTS: 200, observedTS: 210, observerID: "obs2", hash: "h2"},
+		{advertTS: 200, observedTS: 200, observerID: "obs3", hash: "h2"},
+	}
+	offsets, _ := calibrateObservers(samples)
+	if offsets["obs1"] != 0 {
+		t.Errorf("obs1 offset = %v, want 0", offsets["obs1"])
+	}
+	if offsets["obs2"] != 10 {
+		t.Errorf("obs2 offset = %v, want 10", offsets["obs2"])
+	}
+	if offsets["obs3"] != 0 {
+		t.Errorf("obs3 offset = %v, want 0", offsets["obs3"])
+	}
+}
+
+// ── computeNodeSkew ────────────────────────────────────────────────────────────
+
+func TestComputeNodeSkew_BasicCorrection(t *testing.T) {
+	// Validates observer offset correction direction.
+	//
+	// Setup: node is 60s ahead, obs1 accurate, obs2 is 10s ahead.
+	// With 2 observers, median obs_ts = 1005.
+	//   obs1 offset = 1000 - 1005 = -5
+	//   obs2 offset = 1010 - 1005 = +5
+	// Correction: corrected = raw_skew + obsOffset
+	//   obs1: raw=60, corrected = 60 + (-5) = 55
+	//   obs2: raw=50, corrected = 50 + 5 = 55
+	// Both converge to 55 (not exact 60 because with only 2 observers,
+	// the median can't fully distinguish which observer is drifted).
+
+	samples := []skewSample{
+		// Same packet seen by accurate obs1 and obs2 (+10s ahead)
+		{advertTS: 1060, observedTS: 1000, observerID: "obs1", hash: "h1"},
+		{advertTS: 1060, observedTS: 1010, observerID: "obs2", hash: "h1"},
+	}
+	offsets, _ := calibrateObservers(samples)
+	// median obs = 1005, obs1 offset = -5, obs2 offset = +5
+	// So the median approach finds obs2 is +5 ahead (relative to median)
+
+	// Now compute node skew with those offsets:
+	nodeSkew := computeNodeSkew(samples, offsets)
+	cs, ok := nodeSkew["h1"]
+	if !ok {
+		t.Fatal("expected skew data for hash h1")
+	}
+	// With only 2 observers, median obs_ts = 1005.
+	// obs1 offset = 1000-1005 = -5, obs2 offset = 1010-1005 = +5
+	// raw from obs1 = 60, corrected = 60 + (-5) = 55
+	// raw from obs2 = 50, corrected = 50 + 5 = 55
+	// median = 55
+	if cs.MedianSkewSec != 55 {
+		t.Errorf("median skew = %v, want 55", cs.MedianSkewSec)
+	}
+}
+
+func TestComputeNodeSkew_ThreeObservers(t *testing.T) {
+	// Node is exactly 60s ahead. obs1 accurate, obs2 accurate, obs3 +30s ahead.
+	// advertTS = 1060, real time = 1000
+	samples := []skewSample{
+		{advertTS: 1060, observedTS: 1000, observerID: "obs1", hash: "h1"},
+		{advertTS: 1060, observedTS: 1000, observerID: "obs2", hash: "h1"},
+		{advertTS: 1060, observedTS: 1030, observerID: "obs3", hash: "h1"},
+	}
+	offsets, _ := calibrateObservers(samples)
+	// median obs_ts = 1000. obs1=0, obs2=0, obs3=+30
+	if offsets["obs3"] != 30 {
+		t.Errorf("obs3 offset = %v, want 30", offsets["obs3"])
+	}
+
+	nodeSkew := computeNodeSkew(samples, offsets)
+	cs := nodeSkew["h1"]
+	if cs == nil {
+		t.Fatal("expected skew data for h1")
+	}
+	// raw from obs1 = 60, corrected = 60 + 0 = 60
+	// raw from obs2 = 60, corrected = 60 + 0 = 60
+	// raw from obs3 = 30, corrected = 30 + 30 = 60
+	// All three converge to 60. 
+	if cs.MedianSkewSec != 60 {
+		t.Errorf("median skew = %v, want 60 (node is 60s ahead)", cs.MedianSkewSec)
+	}
+}
+
+// ── computeDrift ───────────────────────────────────────────────────────────────
+
+func TestComputeDrift_Stable(t *testing.T) {
+	// Constant skew = no drift.
+	pairs := []tsSkewPair{
+		{ts: 0, skew: 60},
+		{ts: 7200, skew: 60},
+		{ts: 14400, skew: 60},
+	}
+	drift := computeDrift(pairs)
+	if drift != 0 {
+		t.Errorf("drift = %v, want 0 for stable skew", drift)
+	}
+}
+
+func TestComputeDrift_LinearDrift(t *testing.T) {
+	// 1 second drift per hour = 24 sec/day.
+	pairs := []tsSkewPair{
+		{ts: 0, skew: 0},
+		{ts: 3600, skew: 1},
+		{ts: 7200, skew: 2},
+	}
+	drift := computeDrift(pairs)
+	expected := 24.0
+	if math.Abs(drift-expected) > 0.1 {
+		t.Errorf("drift = %v, want ~%v", drift, expected)
+	}
+}
+
+func TestComputeDrift_TooFewSamples(t *testing.T) {
+	pairs := []tsSkewPair{{ts: 0, skew: 10}}
+	if computeDrift(pairs) != 0 {
+		t.Error("expected 0 drift for single sample")
+	}
+}
+
+func TestComputeDrift_TooShortSpan(t *testing.T) {
+	// Less than 1 hour apart.
+	pairs := []tsSkewPair{
+		{ts: 0, skew: 0},
+		{ts: 1800, skew: 10},
+	}
+	if computeDrift(pairs) != 0 {
+		t.Error("expected 0 drift for short time span")
+	}
+}
+
+// ── jsonNumber ─────────────────────────────────────────────────────────────────
+
+func TestJsonNumber(t *testing.T) {
+	m := map[string]interface{}{
+		"a": float64(42),
+		"b": int64(99),
+		"c": "not a number",
+		"d": nil,
+	}
+	if jsonNumber(m, "a") != 42 {
+		t.Error("float64 case failed")
+	}
+	if jsonNumber(m, "b") != 99 {
+		t.Error("int64 case failed")
+	}
+	if jsonNumber(m, "c") != 0 {
+		t.Error("string case should return 0")
+	}
+	if jsonNumber(m, "d") != 0 {
+		t.Error("nil case should return 0")
+	}
+	if jsonNumber(m, "missing") != 0 {
+		t.Error("missing key should return 0")
+	}
+}
+
+// ── Integration: GetNodeClockSkew via PacketStore ──────────────────────────────
+
+func TestGetNodeClockSkew_Integration(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+
+	// Simulate two ADVERT transmissions for the same node, seen by 2 observers each.
+	// Node "AABB" has clock 120s ahead.
+	pt := 4 // ADVERT
+	tx1 := &StoreTx{
+		Hash:        "hash1",
+		PayloadType: &pt,
+		DecodedJSON: `{"payload":{"timestamp":1700002320}}`, // obs=1700002200, node ahead by 120s
+		Observations: []*StoreObs{
+			{ObserverID: "obs1", Timestamp: "2023-11-14T22:50:00Z"}, // 1700002200
+			{ObserverID: "obs2", Timestamp: "2023-11-14T22:50:00Z"}, // 1700002200
+		},
+	}
+	tx2 := &StoreTx{
+		Hash:        "hash2",
+		PayloadType: &pt,
+		DecodedJSON: `{"payload":{"timestamp":1700005920}}`, // obs=1700005800, node ahead by 120s
+		Observations: []*StoreObs{
+			{ObserverID: "obs1", Timestamp: "2023-11-14T23:50:00Z"}, // 1700005800
+			{ObserverID: "obs2", Timestamp: "2023-11-14T23:50:00Z"}, // 1700005800
+		},
+	}
+
+	ps.mu.Lock()
+	ps.byNode["AABB"] = []*StoreTx{tx1, tx2}
+	ps.byPayloadType[4] = []*StoreTx{tx1, tx2}
+	// Force recompute by setting interval to 0.
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	result := ps.GetNodeClockSkew("AABB")
+	if result == nil {
+		t.Fatal("expected clock skew result for node AABB")
+	}
+	if result.Pubkey != "AABB" {
+		t.Errorf("pubkey = %q, want AABB", result.Pubkey)
+	}
+	// Both transmissions show 120s skew, so median should be 120.
+	if result.MedianSkewSec != 120 {
+		t.Errorf("median skew = %v, want 120", result.MedianSkewSec)
+	}
+	if result.SampleCount < 2 {
+		t.Errorf("sample count = %v, want >= 2", result.SampleCount)
+	}
+	if result.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok (120s < 5min)", result.Severity)
+	}
+	// Drift should be ~0 since skew is constant.
+	if math.Abs(result.DriftPerDaySec) > 1 {
+		t.Errorf("drift = %v, want ~0 for constant skew", result.DriftPerDaySec)
+	}
+}
+
+func TestGetNodeClockSkew_NoData(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	result := ps.GetNodeClockSkew("nonexistent")
+	if result != nil {
+		t.Error("expected nil for nonexistent node")
+	}
+}
+
+// ── Sanity check tests (#XXX — clock skew crazy stats) ────────────────────────
+
+func TestGetNodeClockSkew_NoClock_EpochZero(t *testing.T) {
+	// Node with epoch-0 timestamp produces huge skew → no_clock severity, drift=0.
+	ps := NewPacketStore(nil, nil)
+	pt := 4 // ADVERT
+
+	// Epoch-ish advert: advertTS near start of 2020, observed in 2023 → |skew| > 365 days
+	var txs []*StoreTx
+	baseObs := int64(1700000000) // ~Nov 2023
+	for i := 0; i < 6; i++ {
+		obsTS := baseObs + int64(i)*7200
+		tx := &StoreTx{
+			Hash:        "epoch-h" + string(rune('0'+i)),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":1577836800}}`, // Jan 1 2020 — valid but way off
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+
+	ps.mu.Lock()
+	ps.byNode["EPOCH"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	result := ps.GetNodeClockSkew("EPOCH")
+	if result == nil {
+		t.Fatal("expected clock skew result for epoch-0 node")
+	}
+	if result.Severity != SkewNoClock {
+		t.Errorf("severity = %v, want no_clock", result.Severity)
+	}
+	if result.DriftPerDaySec != 0 {
+		t.Errorf("drift = %v, want 0 for no_clock node", result.DriftPerDaySec)
+	}
+}
+
+func TestGetNodeClockSkew_TooFewSamplesForDrift(t *testing.T) {
+	// Node with only 2 advert samples → drift should not be computed.
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 2; i++ {
+		obsTS := baseObs + int64(i)*7200
+		advTS := obsTS + 120 // 120s ahead
+		tx := &StoreTx{
+			Hash:        "few-h" + string(rune('0'+i)),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+
+	ps.mu.Lock()
+	ps.byNode["FEWSAMP"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	result := ps.GetNodeClockSkew("FEWSAMP")
+	if result == nil {
+		t.Fatal("expected clock skew result")
+	}
+	if result.DriftPerDaySec != 0 {
+		t.Errorf("drift = %v, want 0 for 2-sample node (minimum is %d)", result.DriftPerDaySec, minDriftSamples)
+	}
+}
+
+func TestGetNodeClockSkew_AbsurdDriftCapped(t *testing.T) {
+	// Node with wildly varying skew producing |drift| > 86400 s/day → drift capped to 0.
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	// Create 6 samples with extreme skew variation to produce absurd drift.
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 6; i++ {
+		obsTS := baseObs + int64(i)*3600
+		// Alternate between huge positive and negative skew offsets
+		skewOffset := int64(50000 * (1 - 2*(i%2))) // +50000 or -50000
+		advTS := obsTS + skewOffset
+		tx := &StoreTx{
+			Hash:        "wild-h" + string(rune('0'+i)),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+
+	ps.mu.Lock()
+	ps.byNode["WILD"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	result := ps.GetNodeClockSkew("WILD")
+	if result == nil {
+		t.Fatal("expected clock skew result")
+	}
+	if math.Abs(result.DriftPerDaySec) > maxReasonableDriftPerDay {
+		t.Errorf("drift = %v, should be capped (|drift| > %v)", result.DriftPerDaySec, maxReasonableDriftPerDay)
+	}
+}
+
+func TestGetNodeClockSkew_NormalNodeWithDrift(t *testing.T) {
+	// Normal node with 6 samples and consistent linear drift → drift computed correctly.
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 6; i++ {
+		obsTS := baseObs + int64(i)*7200 // every 2 hours
+		// Drift: 1 sec/hour = 24 sec/day
+		advTS := obsTS + 120 + int64(i) // skew grows by 1s per sample (2h apart)
+		tx := &StoreTx{
+			Hash:        "norm-h" + string(rune('0'+i)),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+
+	ps.mu.Lock()
+	ps.byNode["NORMAL"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	result := ps.GetNodeClockSkew("NORMAL")
+	if result == nil {
+		t.Fatal("expected clock skew result")
+	}
+	if result.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok", result.Severity)
+	}
+	// 1s per 7200s = 12 s/day
+	if result.DriftPerDaySec == 0 {
+		t.Error("expected non-zero drift for linearly drifting node")
+	}
+	if math.Abs(result.DriftPerDaySec) > maxReasonableDriftPerDay {
+		t.Errorf("drift = %v, should be reasonable", result.DriftPerDaySec)
+	}
+}
+
+// formatInt64 is a test helper to format int64 as string for JSON embedding.
+func formatInt64(n int64) string {
+	return fmt.Sprintf("%d", n)
+}
+
+// ── #789: Recent-window severity & robust drift ───────────────────────────────
+
+// TestSeverityUsesRecentNotMedian: 100 historical bad samples (skew=-60s,
+// each ~5min apart) followed by 5 fresh good samples (skew=-1s). All-time
+// median is still huge-ish but recent-window severity must reflect the
+// current healthy state.
+func TestSeverityUsesRecentNotMedian(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 105; i++ {
+		obsTS := baseObs + int64(i)*300 // 5 min apart
+		var skew int64 = -60
+		if i >= 100 {
+			skew = -1 // good samples at the tail
+		}
+		advTS := obsTS + skew
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("recent-h%03d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["RECENT"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("RECENT")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok (recent samples are healthy)", r.Severity)
+	}
+	if math.Abs(r.RecentMedianSkewSec) > 5 {
+		t.Errorf("recentMedianSkewSec = %v, want ~-1", r.RecentMedianSkewSec)
+	}
+	// Historical median should still be retained for context.
+	if math.Abs(r.MedianSkewSec) < 30 {
+		t.Errorf("medianSkewSec = %v, expected historical median to remain large", r.MedianSkewSec)
+	}
+}
+
+// TestDriftRejectsCorrectionJump: 30 minutes of clean linear drift, then a
+// single 60-second skew jump. The pre-jump slope should win — drift must
+// not be catastrophically inflated by the correction event.
+func TestDriftRejectsCorrectionJump(t *testing.T) {
+	pairs := []tsSkewPair{}
+	// 30 min of stable, ~12 sec/day drift: 1s per 7200s.
+	for i := 0; i < 12; i++ {
+		ts := int64(i) * 300
+		skew := float64(i) * (1.0 / 24.0) // ~0.04s per 5min step → 12 s/day
+		pairs = append(pairs, tsSkewPair{ts: ts, skew: skew})
+	}
+	// Wait an hour, then a single 1000-sec correction jump (clearly outlier).
+	pairs = append(pairs, tsSkewPair{ts: 3600 + 12*300, skew: 1000})
+
+	drift := computeDrift(pairs)
+	// Without rejection this would be ~ (1000-0)/(end-0) * 86400 = enormous.
+	if math.Abs(drift) > 100 {
+		t.Errorf("drift = %v, expected small (~12 s/day), correction jump should be filtered", drift)
+	}
+}
+
+// TestTheilSenMatchesOLSWhenClean: on clean linear data Theil-Sen should
+// produce essentially the OLS answer.
+func TestTheilSenMatchesOLSWhenClean(t *testing.T) {
+	// 1 sec drift per hour = 24 sec/day, 20 evenly-spaced samples.
+	pairs := []tsSkewPair{}
+	for i := 0; i < 20; i++ {
+		pairs = append(pairs, tsSkewPair{
+			ts:   int64(i) * 600,
+			skew: float64(i) * (600.0 / 3600.0),
+		})
+	}
+	drift := computeDrift(pairs)
+	if math.Abs(drift-24.0) > 0.25 { // ~1%
+		t.Errorf("drift = %v, want ~24", drift)
+	}
+}
+
+// TestReporterScenario_789: reproduce the exact scenario from issue #789.
+// Reporter saw mean=-52565156, median=-59063561, last=-0.8, sample count
+// 1662, drift +1793549.9 s/day, severity=absurd. After the fix, severity
+// must be ok (recent samples are healthy) and drift must be sane.
+func TestReporterScenario_789(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	// 1657 samples with the bad ~-683-day skew (the historical poison),
+	// then 5 freshly corrected samples at -0.8s — totals 1662.
+	for i := 0; i < 1662; i++ {
+		obsTS := baseObs + int64(i)*60 // 1 min apart
+		var skew int64
+		if i < 1657 {
+			skew = -59063561 // ~ -683 days
+		} else {
+			skew = -1 // corrected (rounded; reporter saw -0.8)
+		}
+		advTS := obsTS + skew
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("rep-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["REPNODE"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("REPNODE")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	// Severity must reflect current health, not the all-time median.
+	if r.Severity != SkewOK && r.Severity != SkewWarning {
+		t.Errorf("severity = %v, want ok/warning (recent samples are healthy)", r.Severity)
+	}
+	if math.Abs(r.RecentMedianSkewSec) > 5 {
+		t.Errorf("recentMedianSkewSec = %v, want near 0", r.RecentMedianSkewSec)
+	}
+	// Drift must not be absurd. The historical jump is one event between
+	// the 1657th and 1658th sample; outlier rejection must contain it.
+	if math.Abs(r.DriftPerDaySec) > maxReasonableDriftPerDay {
+		t.Errorf("drift = %v, must be <= cap %v", r.DriftPerDaySec, maxReasonableDriftPerDay)
+	}
+	// And it should be close to zero (stable historical + stable corrected).
+	if math.Abs(r.DriftPerDaySec) > 1000 {
+		t.Errorf("drift = %v, expected near zero after outlier rejection", r.DriftPerDaySec)
+	}
+	// Historical median is preserved as context.
+	if math.Abs(r.MedianSkewSec) < 1e6 {
+		t.Errorf("medianSkewSec = %v, expected historical poison preserved as context", r.MedianSkewSec)
+	}
+}
+
+// TestBimodalClock_845: 60% good samples → bimodal_clock severity.
+func TestBimodalClock_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	// 6 good samples (-5s each), 4 bad samples (-50000000s each) = 60% good
+	// Interleave so the recent window (last 5) captures both good and bad.
+	skews := []int64{-5, -5, -50000000, -5, -50000000, -5, -50000000, -5, -50000000, -5}
+	for i := 0; i < 10; i++ {
+		obsTS := baseObs + int64(i)*60
+		advTS := obsTS + skews[i]
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("bimodal-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["BIMODAL"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("BIMODAL")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewBimodalClock {
+		t.Errorf("severity = %v, want bimodal_clock", r.Severity)
+	}
+	if math.Abs(r.RecentMedianSkewSec-(-5)) > 1 {
+		t.Errorf("recentMedianSkewSec = %v, want ≈ -5 (median of good samples)", r.RecentMedianSkewSec)
+	}
+	if r.GoodFraction < 0.5 || r.GoodFraction > 0.7 {
+		t.Errorf("goodFraction = %v, want ~0.6", r.GoodFraction)
+	}
+	if r.RecentBadSampleCount < 1 {
+		t.Errorf("recentBadSampleCount = %v, want > 0", r.RecentBadSampleCount)
+	}
+}
+
+// TestAllBad_NoClock_845: all samples bad → no_clock.
+func TestAllBad_NoClock_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 10; i++ {
+		obsTS := baseObs + int64(i)*60
+		advTS := obsTS - 50000000
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("allbad-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["ALLBAD"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("ALLBAD")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewNoClock {
+		t.Errorf("severity = %v, want no_clock", r.Severity)
+	}
+}
+
+// TestMostlyGood_OK_845: 90% good 10% bad → ok (outlier filtered).
+func TestMostlyGood_OK_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	// 9 good at -5s, 1 bad at -50000000s
+	for i := 0; i < 10; i++ {
+		obsTS := baseObs + int64(i)*60
+		var skew int64
+		if i < 9 {
+			skew = -5
+		} else {
+			skew = -50000000
+		}
+		advTS := obsTS + skew
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("mostly-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["MOSTLY"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("MOSTLY")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	// 90% good → normal classification path, median of good samples = -5s → ok
+	if r.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok", r.Severity)
+	}
+	if math.Abs(r.RecentMedianSkewSec-(-5)) > 1 {
+		t.Errorf("recentMedianSkewSec = %v, want ≈ -5", r.RecentMedianSkewSec)
+	}
+}
+
+// TestSingleSample_845: one good sample → ok.
+func TestSingleSample_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+	obsTS := int64(1700000000)
+	advTS := obsTS - 30 // 30s skew
+	tx := &StoreTx{
+		Hash:        "single-0001",
+		PayloadType: &pt,
+		DecodedJSON: `{"payload":{"timestamp":` + formatInt64(advTS) + `}}`,
+		Observations: []*StoreObs{
+			{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+		},
+	}
+	ps.mu.Lock()
+	ps.byNode["SINGLE"] = []*StoreTx{tx}
+	ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("SINGLE")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok", r.Severity)
+	}
+	if r.RecentSampleCount != 1 {
+		t.Errorf("recentSampleCount = %d, want 1", r.RecentSampleCount)
+	}
+	if r.GoodFraction != 1.0 {
+		t.Errorf("goodFraction = %v, want 1.0", r.GoodFraction)
+	}
+}
+
+// TestFiftyFifty_Bimodal_845: 50% good / 50% bad → bimodal_clock.
+func TestFiftyFifty_Bimodal_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 10; i++ {
+		obsTS := baseObs + int64(i)*60
+		var skew int64
+		if i%2 == 0 {
+			skew = -10
+		} else {
+			skew = -50000000
+		}
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("fifty-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(obsTS+skew) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["FIFTY"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("FIFTY")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewBimodalClock {
+		t.Errorf("severity = %v, want bimodal_clock", r.Severity)
+	}
+	if r.GoodFraction < 0.4 || r.GoodFraction > 0.6 {
+		t.Errorf("goodFraction = %v, want ~0.5", r.GoodFraction)
+	}
+}
+
+// TestAllGood_OK_845: all samples good → ok, no bimodal.
+func TestAllGood_OK_845(t *testing.T) {
+	ps := NewPacketStore(nil, nil)
+	pt := 4
+	baseObs := int64(1700000000)
+	var txs []*StoreTx
+	for i := 0; i < 10; i++ {
+		obsTS := baseObs + int64(i)*60
+		tx := &StoreTx{
+			Hash:        fmt.Sprintf("allgood-%04d", i),
+			PayloadType: &pt,
+			DecodedJSON: `{"payload":{"timestamp":` + formatInt64(obsTS-3) + `}}`,
+			Observations: []*StoreObs{
+				{ObserverID: "obs1", Timestamp: time.Unix(obsTS, 0).UTC().Format(time.RFC3339)},
+			},
+		}
+		txs = append(txs, tx)
+	}
+	ps.mu.Lock()
+	ps.byNode["ALLGOOD"] = txs
+	for _, tx := range txs {
+		ps.byPayloadType[4] = append(ps.byPayloadType[4], tx)
+	}
+	ps.clockSkew.computeInterval = 0
+	ps.mu.Unlock()
+
+	r := ps.GetNodeClockSkew("ALLGOOD")
+	if r == nil {
+		t.Fatal("nil result")
+	}
+	if r.Severity != SkewOK {
+		t.Errorf("severity = %v, want ok", r.Severity)
+	}
+	if r.GoodFraction != 1.0 {
+		t.Errorf("goodFraction = %v, want 1.0", r.GoodFraction)
+	}
+	if r.RecentBadSampleCount != 0 {
+		t.Errorf("recentBadSampleCount = %v, want 0", r.RecentBadSampleCount)
+	}
+}

cmd/server/collision_details_test.go

@@ -0,0 +1,131 @@
+package main
+
+import (
+	"testing"
+	"time"
+)
+
+// TestCollisionDetailsIncludeNodePairs verifies that collision details contain
+// the correct prefix and matching node pairs (#757).
+func TestCollisionDetailsIncludeNodePairs(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	// Insert two repeater nodes with the same 3-byte prefix "AABB11"
+	db.conn.Exec(`INSERT INTO nodes (public_key, name, role) VALUES ('aabb11ccdd001122', 'Node Alpha', 'repeater')`)
+	db.conn.Exec(`INSERT INTO nodes (public_key, name, role) VALUES ('aabb11eeff334455', 'Node Beta', 'repeater')`)
+
+	// Add advert transmissions with hash_size=3 path bytes (0x80 = bits 10 → size 3)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('0180aabb11ccdd', 'col_hash_01', ?, 1, 4, '{"pubKey":"aabb11ccdd001122","name":"Node Alpha","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (1, 1, 10.0, -91, '["aabb11"]', ?)`, recentEpoch)
+
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('0180aabb11eeff', 'col_hash_02', ?, 1, 4, '{"pubKey":"aabb11eeff334455","name":"Node Beta","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (2, 1, 9.0, -93, '["aabb11"]', ?)`, recentEpoch)
+
+	store := NewPacketStore(db, nil)
+	store.Load()
+
+	result := store.GetAnalyticsHashCollisions("")
+	bySize, ok := result["by_size"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected by_size map")
+	}
+
+	size3, ok := bySize["3"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected by_size[3] map")
+	}
+
+	collisions, ok := size3["collisions"].([]collisionEntry)
+	if !ok {
+		t.Fatalf("expected collisions as []collisionEntry, got %T", size3["collisions"])
+	}
+
+	// Find our collision
+	var found *collisionEntry
+	for i := range collisions {
+		if collisions[i].Prefix == "AABB11" {
+			found = &collisions[i]
+			break
+		}
+	}
+	if found == nil {
+		t.Fatal("expected collision with prefix AABB11")
+	}
+	if found.Appearances != 2 {
+		t.Errorf("expected 2 appearances, got %d", found.Appearances)
+	}
+	if len(found.Nodes) != 2 {
+		t.Fatalf("expected 2 nodes in collision, got %d", len(found.Nodes))
+	}
+
+	// Verify node pairs
+	pubkeys := map[string]bool{}
+	names := map[string]bool{}
+	for _, n := range found.Nodes {
+		pubkeys[n.PublicKey] = true
+		names[n.Name] = true
+	}
+	if !pubkeys["aabb11ccdd001122"] {
+		t.Error("expected node aabb11ccdd001122 in collision")
+	}
+	if !pubkeys["aabb11eeff334455"] {
+		t.Error("expected node aabb11eeff334455 in collision")
+	}
+	if !names["Node Alpha"] {
+		t.Error("expected Node Alpha in collision")
+	}
+	if !names["Node Beta"] {
+		t.Error("expected Node Beta in collision")
+	}
+}
+
+// TestCollisionDetailsEmptyWhenNoCollisions verifies that collision details are
+// empty when there are no collisions (#757).
+func TestCollisionDetailsEmptyWhenNoCollisions(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	// Insert one repeater node with 3-byte hash
+	db.conn.Exec(`INSERT INTO nodes (public_key, name, role) VALUES ('aabb11ccdd001122', 'Solo Node', 'repeater')`)
+
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('0180aabb11ccdd', 'solo_hash_01', ?, 1, 4, '{"pubKey":"aabb11ccdd001122","name":"Solo Node","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (1, 1, 10.0, -91, '["aabb11"]', ?)`, recentEpoch)
+
+	store := NewPacketStore(db, nil)
+	store.Load()
+
+	result := store.GetAnalyticsHashCollisions("")
+	bySize, ok := result["by_size"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected by_size map")
+	}
+
+	size3, ok := bySize["3"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected by_size[3] map")
+	}
+
+	collisions, ok := size3["collisions"].([]collisionEntry)
+	if !ok {
+		t.Fatalf("expected collisions as []collisionEntry, got %T", size3["collisions"])
+	}
+
+	if len(collisions) != 0 {
+		t.Errorf("expected 0 collisions, got %d", len(collisions))
+	}
+}

cmd/server/config.go

@@ -6,6 +6,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"sync"
 
 	"github.com/meshcore-analyzer/geofilter"
 )
@@ -16,6 +17,17 @@ type Config struct {
 	APIKey  string `json:"apiKey"`
 	DBPath  string `json:"dbPath"`
 
+	// NodeBlacklist is a list of public keys to exclude from all API responses.
+	// Blacklisted nodes are hidden from node lists, search, detail, map, and stats.
+	// Use this to filter out trolls, nodes with offensive names, or nodes
+	// reporting deliberately false data (e.g. wrong GPS position) that the
+	// operator refuses to fix.
+	NodeBlacklist []string `json:"nodeBlacklist"`
+
+	// blacklistSetCached is the lazily-built set version of NodeBlacklist.
+	blacklistSetCached map[string]bool
+	blacklistOnce      sync.Once
+
 	Branding   map[string]interface{} `json:"branding"`
 	Theme      map[string]interface{} `json:"theme"`
 	ThemeDark  map[string]interface{} `json:"themeDark"`
@@ -103,16 +115,18 @@ type NeighborGraphConfig struct {
 // PacketStoreConfig controls in-memory packet store limits.
 type PacketStoreConfig struct {
 	RetentionHours float64 `json:"retentionHours"` // max age of packets in hours (0 = unlimited)
-	MaxMemoryMB    int     `json:"maxMemoryMB"`     // hard memory ceiling in MB (0 = unlimited)
+	MaxMemoryMB                    int `json:"maxMemoryMB"`                    // hard memory ceiling in MB (0 = unlimited)
+	MaxResolvedPubkeyIndexEntries  int `json:"maxResolvedPubkeyIndexEntries"`  // warning threshold for index size (0 = 5M default)
 }
 
 // GeoFilterConfig is an alias for the shared geofilter.Config type.
 type GeoFilterConfig = geofilter.Config
 
 type RetentionConfig struct {
-	NodeDays    int `json:"nodeDays"`
-	PacketDays  int `json:"packetDays"`
-	MetricsDays int `json:"metricsDays"`
+	NodeDays      int `json:"nodeDays"`
+	ObserverDays  int `json:"observerDays"`
+	PacketDays    int `json:"packetDays"`
+	MetricsDays   int `json:"metricsDays"`
 }
 
 // MetricsRetentionDays returns configured metrics retention or 30 days default.
@@ -165,6 +179,15 @@ func (c *Config) NodeDaysOrDefault() int {
 	return 7
 }
 
+// ObserverDaysOrDefault returns the configured retention.observerDays or 14 if not set.
+// A value of -1 means observers are never removed.
+func (c *Config) ObserverDaysOrDefault() int {
+	if c.Retention != nil && c.Retention.ObserverDays != 0 {
+		return c.Retention.ObserverDays
+	}
+	return 14
+}
+
 type HealthThresholds struct {
 	InfraDegradedHours float64 `json:"infraDegradedHours"`
 	InfraSilentHours   float64 `json:"infraSilentHours"`
@@ -338,3 +361,30 @@ func (c *Config) PropagationBufferMs() int {
 	}
 	return 5000
 }
+
+// blacklistSet lazily builds and caches the nodeBlacklist as a set for O(1) lookups.
+// Uses sync.Once to eliminate the data race on first concurrent access.
+func (c *Config) blacklistSet() map[string]bool {
+	c.blacklistOnce.Do(func() {
+		if len(c.NodeBlacklist) == 0 {
+			return
+		}
+		m := make(map[string]bool, len(c.NodeBlacklist))
+		for _, pk := range c.NodeBlacklist {
+			trimmed := strings.ToLower(strings.TrimSpace(pk))
+			if trimmed != "" {
+				m[trimmed] = true
+			}
+		}
+		c.blacklistSetCached = m
+	})
+	return c.blacklistSetCached
+}
+
+// IsBlacklisted returns true if the given public key is in the nodeBlacklist.
+func (c *Config) IsBlacklisted(pubkey string) bool {
+	if c == nil || len(c.NodeBlacklist) == 0 {
+		return false
+	}
+	return c.blacklistSet()[strings.ToLower(strings.TrimSpace(pubkey))]
+}

cmd/server/config_test.go

@@ -365,3 +365,25 @@ func TestPropagationBufferMs(t *testing.T) {
 		}
 	})
 }
+
+func TestObserverDaysOrDefault(t *testing.T) {
+	tests := []struct {
+		name string
+		cfg  *Config
+		want int
+	}{
+		{"nil retention", &Config{}, 14},
+		{"zero observer days", &Config{Retention: &RetentionConfig{ObserverDays: 0}}, 14},
+		{"positive value", &Config{Retention: &RetentionConfig{ObserverDays: 30}}, 30},
+		{"keep forever", &Config{Retention: &RetentionConfig{ObserverDays: -1}}, -1},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := tt.cfg.ObserverDaysOrDefault()
+			if got != tt.want {
+				t.Errorf("ObserverDaysOrDefault() = %d, want %d", got, tt.want)
+			}
+		})
+	}
+}

cmd/server/coverage_test.go

@@ -41,7 +41,7 @@ func setupTestDBv2(t *testing.T) *DB {
 			id INTEGER PRIMARY KEY AUTOINCREMENT, raw_hex TEXT NOT NULL,
 			hash TEXT NOT NULL UNIQUE, first_seen TEXT NOT NULL,
 			route_type INTEGER, payload_type INTEGER, payload_version INTEGER,
-			decoded_json TEXT, created_at TEXT DEFAULT (datetime('now'))
+			decoded_json TEXT, channel_hash TEXT DEFAULT NULL, created_at TEXT DEFAULT (datetime('now'))
 		);
 		CREATE TABLE observations (
 			id INTEGER PRIMARY KEY AUTOINCREMENT,
@@ -585,12 +585,15 @@ func TestHandlePacketsMultiNodeWithStore(t *testing.T) {
 func TestHandlePacketDetailNoStore(t *testing.T) {
 	_, router := setupNoStoreServer(t)
 
+	// With no in-memory store, handlePacketDetail now falls back to the DB
+	// (#827). The seeded transmissions are present in the DB, so by-hash and
+	// by-ID lookups succeed; only truly absent IDs return 404.
 	t.Run("by hash", func(t *testing.T) {
 		req := httptest.NewRequest("GET", "/api/packets/abc123def4567890", nil)
 		w := httptest.NewRecorder()
 		router.ServeHTTP(w, req)
-		if w.Code != 404 {
-			t.Fatalf("expected 404 (no store), got %d: %s", w.Code, w.Body.String())
+		if w.Code != 200 {
+			t.Fatalf("expected 200 (DB fallback), got %d: %s", w.Code, w.Body.String())
 		}
 	})
 
@@ -598,8 +601,8 @@ func TestHandlePacketDetailNoStore(t *testing.T) {
 		req := httptest.NewRequest("GET", "/api/packets/1", nil)
 		w := httptest.NewRecorder()
 		router.ServeHTTP(w, req)
-		if w.Code != 404 {
-			t.Fatalf("expected 404 (no store), got %d: %s", w.Code, w.Body.String())
+		if w.Code != 200 {
+			t.Fatalf("expected 200 (DB fallback), got %d: %s", w.Code, w.Body.String())
 		}
 	})
 
@@ -3217,6 +3220,189 @@ func TestGetNodeHashSizeInfoEdgeCases(t *testing.T) {
 	}
 }
 
+// TestHashSizeTransportRoutePathByteOffset verifies that transport routes (0, 3)
+// read the path byte from offset 5 (after 4 transport code bytes), not offset 1.
+// Regression test for #744 / #722.
+func TestHashSizeTransportRoutePathByteOffset(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	db.conn.Exec(`INSERT INTO observers (id, name, iata, last_seen, first_seen, packet_count)
+		VALUES ('obs1', 'Obs', 'SJC', ?, '2026-01-01T00:00:00Z', 10)`, recent)
+
+	// Route type 0 (TRANSPORT_FLOOD): header=0x04 (payload_type=1, route_type=0)
+	// 4 transport bytes + path byte at offset 5.
+	// Path byte 0x80 → hash_size bits = 10 → size 3
+	// If bug is present, code reads byte 1 (0xAA) → hash_size bits = 10 → size 3 (coincidence)
+	// Use path byte 0x40 (hash_size=2) and transport byte 0x01 at offset 1 (hash_size=1 if misread)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('100102030440aabb', 'tf_offset', ?, 0, 4, '{"pubKey":"aaaa000000000001","name":"TF-Node","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (1, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	// Route type 3 (TRANSPORT_DIRECT): header=0x13 (payload_type=4, route_type=3)
+	// 4 transport bytes + path byte at offset 5.
+	// Path byte 0xC1 → hash_size bits = 11 → size 4, hop_count = 1 (not zero-hop)
+	// Byte 1 = 0x05 → hash_size bits = 00 → size 1 if misread
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1305060708C1bbcc', 'td_offset', ?, 3, 4, '{"pubKey":"aaaa000000000002","name":"TD-Node","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (2, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	// Route type 1 (FLOOD): header=0x11 (payload_type=4, route_type=1)
+	// Path byte at offset 1. Path byte 0x80 → hash_size bits = 10 → size 3
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1180aabbccdd', 'flood_offset', ?, 1, 4, '{"pubKey":"aaaa000000000003","name":"Flood-Node","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (3, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	store := NewPacketStore(db, nil)
+	store.Load()
+	info := store.GetNodeHashSizeInfo()
+
+	// Transport flood node: path byte 0x40 → hash_size = 2
+	if ni, ok := info["aaaa000000000001"]; !ok {
+		t.Error("transport flood node missing from hash size info")
+	} else if ni.HashSize != 2 {
+		t.Errorf("transport flood node: want HashSize=2 (from path byte at offset 5), got %d", ni.HashSize)
+	}
+
+	// Transport direct node: path byte 0xC1 → hash_size = 4
+	if ni, ok := info["aaaa000000000002"]; !ok {
+		t.Error("transport direct node missing from hash size info")
+	} else if ni.HashSize != 4 {
+		t.Errorf("transport direct node: want HashSize=4 (from path byte at offset 5), got %d", ni.HashSize)
+	}
+
+	// Regular flood node: path byte 0x80 → hash_size = 3
+	if ni, ok := info["aaaa000000000003"]; !ok {
+		t.Error("regular flood node missing from hash size info")
+	} else if ni.HashSize != 3 {
+		t.Errorf("regular flood node: want HashSize=3 (from path byte at offset 1), got %d", ni.HashSize)
+	}
+}
+
+// TestHashSizeTransportDirectZeroHopSkipped verifies that RouteTransportDirect
+// zero-hop adverts are skipped (same as RouteDirect). Regression test for #744.
+func TestHashSizeTransportDirectZeroHopSkipped(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	db.conn.Exec(`INSERT INTO observers (id, name, iata, last_seen, first_seen, packet_count)
+		VALUES ('obs1', 'Obs', 'SJC', ?, '2026-01-01T00:00:00Z', 10)`, recent)
+
+	// RouteDirect (2) zero-hop: path byte 0x40 → hop_count=0, hash_size bits=01
+	// Should be skipped (existing behavior)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1240aabbccdd', 'direct_zh', ?, 2, 4, '{"pubKey":"bbbb000000000001","name":"Direct-ZH","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (1, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	// RouteTransportDirect (3) zero-hop: 4 transport bytes + path byte 0x40 → hop_count=0
+	// Should ALSO be skipped (this was the missing case)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('130102030440aabb', 'tdirect_zh', ?, 3, 4, '{"pubKey":"bbbb000000000002","name":"TDirect-ZH","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (2, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	// RouteDirect (2) non-zero-hop: path byte 0x41 → hop_count=1
+	// Should NOT be skipped
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1241aabbccdd', 'direct_1h', ?, 2, 4, '{"pubKey":"bbbb000000000003","name":"Direct-1H","type":"ADVERT"}')`, recent)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (3, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	store := NewPacketStore(db, nil)
+	store.Load()
+	info := store.GetNodeHashSizeInfo()
+
+	// RouteDirect zero-hop should be absent
+	if _, ok := info["bbbb000000000001"]; ok {
+		t.Error("RouteDirect zero-hop advert should be skipped")
+	}
+
+	// RouteTransportDirect zero-hop should also be absent
+	if _, ok := info["bbbb000000000002"]; ok {
+		t.Error("RouteTransportDirect zero-hop advert should be skipped")
+	}
+
+	// RouteDirect non-zero-hop should be present with hash_size=2
+	if ni, ok := info["bbbb000000000003"]; !ok {
+		t.Error("RouteDirect non-zero-hop should be in hash size info")
+	} else if ni.HashSize != 2 {
+		t.Errorf("RouteDirect non-zero-hop: want HashSize=2, got %d", ni.HashSize)
+	}
+}
+
+// TestAnalyticsHashSizesZeroHopSkip verifies that computeAnalyticsHashSizes
+// does not overwrite a node's hash_size with a zero-hop advert's unreliable value.
+// Regression test for #744.
+func TestAnalyticsHashSizesZeroHopSkip(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	db.conn.Exec(`INSERT INTO observers (id, name, iata, last_seen, first_seen, packet_count)
+		VALUES ('obs1', 'Obs', 'SJC', ?, '2026-01-01T00:00:00Z', 10)`, recent)
+
+	pk := "cccc000000000001"
+	db.conn.Exec(`INSERT INTO nodes (public_key, name, role) VALUES (?, 'ZH-Analytics', 'repeater')`, pk)
+
+	decoded := `{"pubKey":"` + pk + `","name":"ZH-Analytics","type":"ADVERT"}`
+
+	// First: a flood advert with hashSize=2 (reliable, multi-hop)
+	// header 0x11 = route_type 1 (flood), payload_type 4
+	// pathByte 0x41 = hashSize bits 01 → size 2, hop_count 1
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1141aabbccdd', 'az_flood', ?, 1, 4, ?)`, recent, decoded)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (1, 1, 10.0, -90, '["aabb"]', ?)`, recentEpoch)
+
+	// Second: a direct zero-hop advert with pathByte=0x00 → would give hashSize=1
+	// header 0x12 = route_type 2 (direct), payload_type 4
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('1200aabbccdd', 'az_direct', ?, 2, 4, ?)`, recent, decoded)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (2, 1, 10.0, -90, '[]', ?)`, recentEpoch)
+
+	store := NewPacketStore(db, nil)
+	store.Load()
+
+	result := store.GetAnalyticsHashSizes("")
+
+	// The node should appear in multiByteNodes (hashSize=2 from the flood advert)
+	// If the zero-hop bug is present, hashSize would be 1 and the node would NOT
+	// appear in multiByteNodes.
+	multiByteNodes, ok := result["multiByteNodes"].([]map[string]interface{})
+	if !ok {
+		t.Fatal("expected multiByteNodes slice in analytics hash sizes")
+	}
+
+	found := false
+	for _, n := range multiByteNodes {
+		if n["pubkey"] == pk {
+			found = true
+			if hs, ok := n["hashSize"].(int); ok && hs != 2 {
+				t.Errorf("expected hashSize=2 from flood advert, got %d", hs)
+			}
+		}
+	}
+	if !found {
+		t.Error("node should appear in multiByteNodes with hashSize=2; zero-hop advert should not overwrite to 1")
+	}
+}
+
 func TestHandleResolveHopsEdgeCases(t *testing.T) {
 	db := setupTestDB(t)
 	defer db.Close()
@@ -4133,88 +4319,48 @@ func TestIndexByNodePreCheck(t *testing.T) {
 	})
 }
 
-// TestIndexByNodeResolvedPath tests that resolved_path entries are indexed in byNode.
+// TestIndexByNodeResolvedPath tests that indexByNode only indexes decoded JSON pubkeys.
+// After #800, resolved_path entries are handled via the decode-window, not indexByNode.
 func TestIndexByNodeResolvedPath(t *testing.T) {
 	store := &PacketStore{
 		byNode:     make(map[string][]*StoreTx),
 		nodeHashes: make(map[string]map[string]bool),
 	}
 
-	t.Run("indexes resolved path pubkeys from observations", func(t *testing.T) {
-		relayPK := "aabb1122334455ff"
+	t.Run("decoded JSON pubkeys still indexed", func(t *testing.T) {
+		pk := "aabb1122334455ff"
 		tx := &StoreTx{
 			Hash:        "rp1",
-			DecodedJSON: `{"type":"CHAN","text":"hello"}`, // no pubKey fields
-			Observations: []*StoreObs{
-				{ResolvedPath: []*string{&relayPK}},
-			},
-		}
-		store.indexByNode(tx)
-		if len(store.byNode[relayPK]) != 1 {
-			t.Errorf("expected relay pubkey indexed, got %d", len(store.byNode[relayPK]))
-		}
-	})
-
-	t.Run("skips null entries in resolved path", func(t *testing.T) {
-		pk := "cc11dd22ee33ff44"
-		tx := &StoreTx{
-			Hash: "rp2",
-			Observations: []*StoreObs{
-				{ResolvedPath: []*string{nil, &pk, nil}},
-			},
+			DecodedJSON: `{"pubKey":"` + pk + `"}`,
 		}
 		store.indexByNode(tx)
 		if len(store.byNode[pk]) != 1 {
-			t.Errorf("expected resolved pubkey indexed, got %d", len(store.byNode[pk]))
-		}
-		// Verify nil entries didn't create empty-string keys
-		if _, exists := store.byNode[""]; exists {
-			t.Error("nil/empty resolved path entries should not create byNode entries")
+			t.Errorf("expected decoded pubkey indexed, got %d", len(store.byNode[pk]))
 		}
 	})
 
-	t.Run("relay-only node appears in byNode", func(t *testing.T) {
-		// A packet with no decoded pubkey fields, only a relay in resolved path
-		relayOnly := "relay0only0pubkey"
+	t.Run("resolved path pubkeys NOT indexed by indexByNode", func(t *testing.T) {
+		// After #800, indexByNode only handles decoded JSON fields.
+		// Resolved path pubkeys are handled by the decode-window.
 		tx := &StoreTx{
-			Hash: "rp3",
-			// No DecodedJSON at all — pure relay
-			Observations: []*StoreObs{
-				{ResolvedPath: []*string{&relayOnly}},
-			},
+			Hash:        "rp2",
+			DecodedJSON: `{"type":"CHAN","text":"hello"}`, // no pubKey fields
 		}
 		store.indexByNode(tx)
-		if len(store.byNode[relayOnly]) != 1 {
-			t.Errorf("expected relay-only node indexed, got %d", len(store.byNode[relayOnly]))
-		}
+		// No new entries expected since there are no decoded pubkeys
 	})
 
-	t.Run("dedup between decoded JSON and resolved path", func(t *testing.T) {
+	t.Run("dedup within decoded JSON", func(t *testing.T) {
 		pk := "dedup0test0pk1234"
 		tx := &StoreTx{
 			Hash:        "rp4",
-			DecodedJSON: `{"pubKey":"` + pk + `"}`,
-			Observations: []*StoreObs{
-				{ResolvedPath: []*string{&pk}},
-			},
+			DecodedJSON: `{"pubKey":"` + pk + `","destPubKey":"` + pk + `"}`,
 		}
 		store.indexByNode(tx)
 		if len(store.byNode[pk]) != 1 {
 			t.Errorf("expected dedup to keep 1 entry, got %d", len(store.byNode[pk]))
 		}
 	})
-
-	t.Run("indexes tx.ResolvedPath when observations empty", func(t *testing.T) {
-		rpPK := "txlevel0resolved1"
-		tx := &StoreTx{
-			Hash:         "rp5",
-			ResolvedPath: []*string{&rpPK},
-		}
-		store.indexByNode(tx)
-		if len(store.byNode[rpPK]) != 1 {
-			t.Errorf("expected tx-level resolved path indexed, got %d", len(store.byNode[rpPK]))
-		}
-	})
 }
 
 // BenchmarkIndexByNode measures indexByNode performance with and without pubkey

cmd/server/db.go

@@ -8,6 +8,7 @@ import (
 	"math"
 	"os"
 	"strings"
+	"sync"
 	"time"
 
 	_ "modernc.org/sqlite"
@@ -19,6 +20,12 @@ type DB struct {
 	path             string // filesystem path to the database file
 	isV3             bool   // v3 schema: observer_idx in observations (vs observer_id in v2)
 	hasResolvedPath  bool   // observations table has resolved_path column
+
+	// Channel list cache (60s TTL) — avoids repeated GROUP BY scans (#762)
+	channelsCacheMu  sync.Mutex
+	channelsCacheKey string
+	channelsCacheRes []map[string]interface{}
+	channelsCacheExp time.Time
 }
 
 // OpenDB opens a read-only SQLite connection with WAL mode.
@@ -377,6 +384,7 @@ type PacketQuery struct {
 	Until    string
 	Region   string
 	Node     string
+	Channel  string // channel_hash filter (#812). Plain names like "#test"/"public" or "enc_<HEX>" for encrypted
 	Order               string // ASC or DESC
 	ExpandObservations  bool   // when true, include observation sub-maps in txToMap output
 }
@@ -613,6 +621,11 @@ func (db *DB) buildTransmissionWhere(q PacketQuery) ([]string, []interface{}) {
 		where = append(where, "t.decoded_json LIKE ?")
 		args = append(args, "%"+pk+"%")
 	}
+	if q.Channel != "" {
+		// channel_hash column is indexed for payload_type = 5; filter is exact match.
+		where = append(where, "t.channel_hash = ?")
+		args = append(args, q.Channel)
+	}
 	if q.Observer != "" {
 		ids := strings.Split(q.Observer, ",")
 		placeholders := strings.Repeat("?,", len(ids))
@@ -679,6 +692,20 @@ func (db *DB) GetPacketByHash(hash string) (map[string]interface{}, error) {
 	return nil, nil
 }
 
+// GetObservationsForHash returns all observations for the transmission with
+// the given content hash. Used as a fallback by the packet-detail handler
+// when the in-memory PacketStore has pruned the entry but the DB still has it.
+func (db *DB) GetObservationsForHash(hash string) []map[string]interface{} {
+	var txID int
+	err := db.conn.QueryRow("SELECT id FROM transmissions WHERE hash = ?",
+		strings.ToLower(hash)).Scan(&txID)
+	if err != nil {
+		return nil
+	}
+	obsByTx := db.getObservationsForTransmissions([]int{txID})
+	return obsByTx[txID]
+}
+
 
 // GetNodes returns filtered, paginated node list.
 func (db *DB) GetNodes(limit, offset int, role, search, before, lastHeard, sortBy, region string) ([]map[string]interface{}, int, map[string]int, error) {
@@ -1153,69 +1180,219 @@ func (db *DB) GetTraces(hash string) ([]map[string]interface{}, error) {
 // Queries transmissions directly (not a VIEW) to avoid observation-level
 // duplicates that could cause stale lastMessage when an older message has
 // a later re-observation timestamp.
-func (db *DB) GetChannels() ([]map[string]interface{}, error) {
-	rows, err := db.conn.Query(`SELECT decoded_json, first_seen FROM transmissions WHERE payload_type = 5 ORDER BY first_seen ASC`)
+func (db *DB) GetChannels(region ...string) ([]map[string]interface{}, error) {
+	regionParam := ""
+	if len(region) > 0 {
+		regionParam = region[0]
+	}
+
+	// Check cache (60s TTL)
+	db.channelsCacheMu.Lock()
+	if db.channelsCacheRes != nil && db.channelsCacheKey == regionParam && time.Now().Before(db.channelsCacheExp) {
+		res := db.channelsCacheRes
+		db.channelsCacheMu.Unlock()
+		return res, nil
+	}
+	db.channelsCacheMu.Unlock()
+
+	regionCodes := normalizeRegionCodes(regionParam)
+
+	var querySQL string
+	args := make([]interface{}, 0, len(regionCodes))
+
+	if len(regionCodes) > 0 {
+		placeholders := make([]string, len(regionCodes))
+		for i, code := range regionCodes {
+			placeholders[i] = "?"
+			args = append(args, code)
+		}
+		regionPlaceholder := strings.Join(placeholders, ",")
+		if db.isV3 {
+			querySQL = fmt.Sprintf(`SELECT t.channel_hash,
+					COUNT(*) AS msg_count,
+					MAX(t.first_seen) AS last_activity,
+					(SELECT t2.decoded_json FROM transmissions t2
+					 WHERE t2.channel_hash = t.channel_hash AND t2.payload_type = 5
+					 ORDER BY t2.first_seen DESC LIMIT 1) AS sample_json
+				FROM transmissions t
+				JOIN observations o ON o.transmission_id = t.id
+				LEFT JOIN observers obs ON obs.rowid = o.observer_idx
+				WHERE t.payload_type = 5
+				AND t.channel_hash IS NOT NULL
+				AND t.channel_hash NOT LIKE 'enc_%%'
+				AND obs.rowid IS NOT NULL AND UPPER(TRIM(obs.iata)) IN (%s)
+				GROUP BY t.channel_hash
+				ORDER BY last_activity DESC`, regionPlaceholder)
+		} else {
+			querySQL = fmt.Sprintf(`SELECT t.channel_hash,
+					COUNT(*) AS msg_count,
+					MAX(t.first_seen) AS last_activity,
+					(SELECT t2.decoded_json FROM transmissions t2
+					 WHERE t2.channel_hash = t.channel_hash AND t2.payload_type = 5
+					 ORDER BY t2.first_seen DESC LIMIT 1) AS sample_json
+				FROM transmissions t
+				JOIN observations o ON o.transmission_id = t.id
+				WHERE t.payload_type = 5
+				AND t.channel_hash IS NOT NULL
+				AND t.channel_hash NOT LIKE 'enc_%%'
+				AND EXISTS (
+					SELECT 1 FROM observers obs
+					WHERE obs.id = o.observer_id
+					AND UPPER(TRIM(obs.iata)) IN (%s)
+				)
+				GROUP BY t.channel_hash
+				ORDER BY last_activity DESC`, regionPlaceholder)
+		}
+	} else {
+		querySQL = `SELECT channel_hash,
+				COUNT(*) AS msg_count,
+				MAX(first_seen) AS last_activity,
+				(SELECT t2.decoded_json FROM transmissions t2
+				 WHERE t2.channel_hash = t.channel_hash AND t2.payload_type = 5
+				 ORDER BY t2.first_seen DESC LIMIT 1) AS sample_json
+			FROM transmissions t
+			WHERE payload_type = 5
+			AND channel_hash IS NOT NULL
+			AND channel_hash NOT LIKE 'enc_%%'
+			GROUP BY channel_hash
+			ORDER BY last_activity DESC`
+	}
+
+	rows, err := db.conn.Query(querySQL, args...)
 	if err != nil {
 		return nil, err
 	}
 	defer rows.Close()
 
-	channelMap := map[string]map[string]interface{}{}
+	channels := make([]map[string]interface{}, 0)
 	for rows.Next() {
-		var dj, fs sql.NullString
-		rows.Scan(&dj, &fs)
-		if !dj.Valid {
+		var chHash, lastActivity, sampleJSON sql.NullString
+		var msgCount int
+		if err := rows.Scan(&chHash, &msgCount, &lastActivity, &sampleJSON); err != nil {
 			continue
 		}
-		var decoded map[string]interface{}
-		if json.Unmarshal([]byte(dj.String), &decoded) != nil {
-			continue
-		}
-		dtype, _ := decoded["type"].(string)
-		if dtype != "CHAN" {
-			continue
-		}
-		// Filter out garbage-decrypted channel names/messages (pre-#197 data still in DB)
-		chanStr, _ := decoded["channel"].(string)
-		textStr, _ := decoded["text"].(string)
-		if hasGarbageChars(chanStr) || hasGarbageChars(textStr) {
-			continue
-		}
-		channelName, _ := decoded["channel"].(string)
+		channelName := nullStr(chHash)
 		if channelName == "" {
-			channelName = "unknown"
+			continue
 		}
-		key := channelName
 
-		ch, exists := channelMap[key]
-		if !exists {
-			ch = map[string]interface{}{
-				"hash": key, "name": channelName,
-				"lastMessage": nil, "lastSender": nil,
-				"messageCount": 0, "lastActivity": nullStr(fs),
-			}
-			channelMap[key] = ch
-		}
-		ch["messageCount"] = ch["messageCount"].(int) + 1
-		if fs.Valid {
-			ch["lastActivity"] = fs.String
-		}
-		if text, ok := decoded["text"].(string); ok && text != "" {
-			idx := strings.Index(text, ": ")
-			if idx > 0 {
-				ch["lastMessage"] = text[idx+2:]
-			} else {
-				ch["lastMessage"] = text
-			}
-			if sender, ok := decoded["sender"].(string); ok {
-				ch["lastSender"] = sender
+		var lastMessage, lastSender interface{}
+		if sampleJSON.Valid {
+			var decoded map[string]interface{}
+			if json.Unmarshal([]byte(sampleJSON.String), &decoded) == nil {
+				if text, ok := decoded["text"].(string); ok && text != "" {
+					idx := strings.Index(text, ": ")
+					if idx > 0 {
+						lastMessage = text[idx+2:]
+					} else {
+						lastMessage = text
+					}
+					if sender, ok := decoded["sender"].(string); ok {
+						lastSender = sender
+					}
+				}
 			}
 		}
+
+		channels = append(channels, map[string]interface{}{
+			"hash": channelName, "name": channelName,
+			"lastMessage": lastMessage, "lastSender": lastSender,
+			"messageCount": msgCount, "lastActivity": nullStr(lastActivity),
+		})
 	}
 
-	channels := make([]map[string]interface{}, 0, len(channelMap))
-	for _, ch := range channelMap {
-		channels = append(channels, ch)
+	// Store in cache (60s TTL)
+	db.channelsCacheMu.Lock()
+	db.channelsCacheRes = channels
+	db.channelsCacheKey = regionParam
+	db.channelsCacheExp = time.Now().Add(60 * time.Second)
+	db.channelsCacheMu.Unlock()
+
+	return channels, nil
+}
+
+// GetEncryptedChannels returns channels where all messages are undecryptable (no key).
+// Uses channel_hash column (prefixed with 'enc_') for fast grouped queries.
+func (db *DB) GetEncryptedChannels(region ...string) ([]map[string]interface{}, error) {
+	regionParam := ""
+	if len(region) > 0 {
+		regionParam = region[0]
+	}
+	regionCodes := normalizeRegionCodes(regionParam)
+
+	var querySQL string
+	args := make([]interface{}, 0, len(regionCodes))
+
+	if len(regionCodes) > 0 {
+		placeholders := make([]string, len(regionCodes))
+		for i, code := range regionCodes {
+			placeholders[i] = "?"
+			args = append(args, code)
+		}
+		regionPlaceholder := strings.Join(placeholders, ",")
+		if db.isV3 {
+			querySQL = fmt.Sprintf(`SELECT t.channel_hash,
+					COUNT(*) AS msg_count,
+					MAX(t.first_seen) AS last_activity
+				FROM transmissions t
+				JOIN observations o ON o.transmission_id = t.id
+				LEFT JOIN observers obs ON obs.rowid = o.observer_idx
+				WHERE t.payload_type = 5
+				AND t.channel_hash LIKE 'enc_%%'
+				AND obs.rowid IS NOT NULL AND UPPER(TRIM(obs.iata)) IN (%s)
+				GROUP BY t.channel_hash
+				ORDER BY last_activity DESC`, regionPlaceholder)
+		} else {
+			querySQL = fmt.Sprintf(`SELECT t.channel_hash,
+					COUNT(*) AS msg_count,
+					MAX(t.first_seen) AS last_activity
+				FROM transmissions t
+				JOIN observations o ON o.transmission_id = t.id
+				WHERE t.payload_type = 5
+				AND t.channel_hash LIKE 'enc_%%'
+				AND EXISTS (
+					SELECT 1 FROM observers obs
+					WHERE obs.id = o.observer_id
+					AND UPPER(TRIM(obs.iata)) IN (%s)
+				)
+				GROUP BY t.channel_hash
+				ORDER BY last_activity DESC`, regionPlaceholder)
+		}
+	} else {
+		querySQL = `SELECT channel_hash,
+				COUNT(*) AS msg_count,
+				MAX(first_seen) AS last_activity
+			FROM transmissions
+			WHERE payload_type = 5
+			AND channel_hash LIKE 'enc_%%'
+			GROUP BY channel_hash
+			ORDER BY last_activity DESC`
+	}
+
+	rows, err := db.conn.Query(querySQL, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	channels := make([]map[string]interface{}, 0)
+	for rows.Next() {
+		var chHash, lastActivity sql.NullString
+		var msgCount int
+		if err := rows.Scan(&chHash, &msgCount, &lastActivity); err != nil {
+			continue
+		}
+		fullHash := nullStrVal(chHash) // e.g. "enc_3A"
+		hexPart := strings.TrimPrefix(fullHash, "enc_")
+		channels = append(channels, map[string]interface{}{
+			"hash":         fullHash,
+			"name":         "Encrypted (0x" + hexPart + ")",
+			"lastMessage":  nil,
+			"lastSender":   nil,
+			"messageCount": msgCount,
+			"lastActivity": nullStr(lastActivity),
+			"encrypted":    true,
+		})
 	}
 	return channels, nil
 }
@@ -1244,15 +1421,16 @@ func (db *DB) GetChannelMessages(channelHash string, limit, offset int, region .
 		regionPlaceholders = strings.Join(placeholders, ",")
 	}
 
+	// Fetch messages with channel_hash filter (pagination applied in Go after dedup)
 	var querySQL string
-	args := make([]interface{}, 0, len(regionArgs))
+	args := []interface{}{channelHash}
 	if db.isV3 {
 		querySQL = `SELECT o.id, t.hash, t.decoded_json, t.first_seen,
 				obs.id, obs.name, o.snr, o.path_json
 			FROM observations o
 			JOIN transmissions t ON t.id = o.transmission_id
 			LEFT JOIN observers obs ON obs.rowid = o.observer_idx
-			WHERE t.payload_type = 5`
+			WHERE t.channel_hash = ? AND t.payload_type = 5`
 		if len(regionCodes) > 0 {
 			querySQL += fmt.Sprintf(" AND obs.rowid IS NOT NULL AND UPPER(TRIM(obs.iata)) IN (%s)", regionPlaceholders)
 			args = append(args, regionArgs...)
@@ -1264,14 +1442,11 @@ func (db *DB) GetChannelMessages(channelHash string, limit, offset int, region .
 				o.observer_id, o.observer_name, o.snr, o.path_json
 			FROM observations o
 			JOIN transmissions t ON t.id = o.transmission_id
-			WHERE t.payload_type = 5`
+			WHERE t.channel_hash = ? AND t.payload_type = 5`
 		if len(regionCodes) > 0 {
 			querySQL += fmt.Sprintf(` AND EXISTS (
-				SELECT 1
-				FROM observers obs
-				WHERE obs.id = o.observer_id
-				AND UPPER(TRIM(obs.iata)) IN (%s)
-			)`, regionPlaceholders)
+				SELECT 1 FROM observers obs WHERE obs.id = o.observer_id
+				AND UPPER(TRIM(obs.iata)) IN (%s))`, regionPlaceholders)
 			args = append(args, regionArgs...)
 		}
 		querySQL += `
@@ -1303,17 +1478,6 @@ func (db *DB) GetChannelMessages(channelHash string, limit, offset int, region .
 		if json.Unmarshal([]byte(dj.String), &decoded) != nil {
 			continue
 		}
-		dtype, _ := decoded["type"].(string)
-		if dtype != "CHAN" {
-			continue
-		}
-		ch, _ := decoded["channel"].(string)
-		if ch == "" {
-			ch = "unknown"
-		}
-		if ch != channelHash {
-			continue
-		}
 
 		text, _ := decoded["text"].(string)
 		sender, _ := decoded["sender"].(string)
@@ -1373,18 +1537,18 @@ func (db *DB) GetChannelMessages(channelHash string, limit, offset int, region .
 		}
 	}
 
-	total := len(msgOrder)
-	// Return latest messages (tail)
-	start := total - limit - offset
+	// Return latest messages (tail) with pagination
+	msgTotal := len(msgOrder)
+	start := msgTotal - limit - offset
 	if start < 0 {
 		start = 0
 	}
-	end := total - offset
+	end := msgTotal - offset
 	if end < 0 {
 		end = 0
 	}
-	if end > total {
-		end = total
+	if end > msgTotal {
+		end = msgTotal
 	}
 
 	messages := make([]map[string]interface{}, 0)
@@ -1395,7 +1559,7 @@ func (db *DB) GetChannelMessages(channelHash string, limit, offset int, region .
 		messages = append(messages, m.Data)
 	}
 
-	return messages, total, nil
+	return messages, msgTotal, nil
 }
 
 
@@ -2069,6 +2233,35 @@ func (db *DB) PruneOldMetrics(retentionDays int) (int64, error) {
 	return n, nil
 }
 
+// RemoveStaleObservers marks observers that have not actively sent data in observerDays
+// as inactive (soft-delete). This preserves JOIN integrity for observations.observer_idx
+// and observer_metrics.observer_id — historical data still references the correct observer.
+// An observer must actively send data to stay listed — being seen by another node does not count.
+// observerDays <= -1 means never remove (keep forever).
+func (db *DB) RemoveStaleObservers(observerDays int) (int64, error) {
+	if observerDays <= -1 {
+		return 0, nil // keep forever
+	}
+	rw, err := openRW(db.path)
+	if err != nil {
+		return 0, err
+	}
+	defer rw.Close()
+
+	cutoff := time.Now().UTC().AddDate(0, 0, -observerDays).Format(time.RFC3339)
+	res, err := rw.Exec(`UPDATE observers SET inactive = 1 WHERE last_seen < ? AND (inactive IS NULL OR inactive = 0)`, cutoff)
+	if err != nil {
+		return 0, err
+	}
+	n, _ := res.RowsAffected()
+	if n > 0 {
+		// Clean up orphaned metrics for now-inactive observers
+		rw.Exec(`DELETE FROM observer_metrics WHERE observer_id IN (SELECT id FROM observers WHERE inactive = 1)`)
+		log.Printf("[observers] Marked %d observer(s) as inactive (not seen in %d days)", n, observerDays)
+	}
+	return n, nil
+}
+
 // TouchNodeLastSeen updates last_seen for a node identified by full public key.
 // Only updates if the new timestamp is newer than the existing value (or NULL).
 // Returns nil even if no rows are affected (node doesn't exist).
@@ -2079,3 +2272,71 @@ func (db *DB) TouchNodeLastSeen(pubkey string, timestamp string) error {
 	)
 	return err
 }
+
+// GetDroppedPackets returns recently dropped packets, newest first.
+func (db *DB) GetDroppedPackets(limit int, observerID, nodePubkey string) ([]map[string]interface{}, error) {
+	if limit <= 0 || limit > 500 {
+		limit = 100
+	}
+	query := `SELECT id, hash, raw_hex, reason, observer_id, observer_name, node_pubkey, node_name, dropped_at FROM dropped_packets`
+	var conditions []string
+	var args []interface{}
+	if observerID != "" {
+		conditions = append(conditions, "observer_id = ?")
+		args = append(args, observerID)
+	}
+	if nodePubkey != "" {
+		conditions = append(conditions, "node_pubkey = ?")
+		args = append(args, nodePubkey)
+	}
+	if len(conditions) > 0 {
+		query += " WHERE " + strings.Join(conditions, " AND ")
+	}
+	query += " ORDER BY dropped_at DESC LIMIT ?"
+	args = append(args, limit)
+
+	rows, err := db.conn.Query(query, args...)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var results []map[string]interface{}
+	for rows.Next() {
+		var id int
+		var hash, rawHex, reason, obsID, obsName, pubkey, name, droppedAt sql.NullString
+		if err := rows.Scan(&id, &hash, &rawHex, &reason, &obsID, &obsName, &pubkey, &name, &droppedAt); err != nil {
+			continue
+		}
+		row := map[string]interface{}{
+			"id":            id,
+			"hash":          nullStr(hash),
+			"reason":        nullStr(reason),
+			"observer_id":   nullStr(obsID),
+			"observer_name": nullStr(obsName),
+			"node_pubkey":   nullStr(pubkey),
+			"node_name":     nullStr(name),
+			"dropped_at":    nullStr(droppedAt),
+		}
+		// Only include raw_hex if explicitly requested (it's large)
+		if rawHex.Valid {
+			row["raw_hex"] = rawHex.String
+		}
+		results = append(results, row)
+	}
+	if results == nil {
+		results = []map[string]interface{}{}
+	}
+	return results, nil
+}
+
+// GetSignatureDropCount returns the total number of dropped packets.
+func (db *DB) GetSignatureDropCount() int64 {
+	var count int64
+	// Table may not exist yet if ingestor hasn't run the migration
+	err := db.conn.QueryRow("SELECT COUNT(*) FROM dropped_packets").Scan(&count)
+	if err != nil {
+		return 0
+	}
+	return count
+}

cmd/server/db_test.go

@@ -60,6 +60,7 @@ func setupTestDB(t *testing.T) *DB {
 			payload_type INTEGER,
 			payload_version INTEGER,
 			decoded_json TEXT,
+			channel_hash TEXT DEFAULT NULL,
 			created_at TEXT DEFAULT (datetime('now'))
 		);
 
@@ -124,10 +125,10 @@ func seedTestData(t *testing.T, db *DB) {
 		VALUES ('1122334455667788', 'TestRoom', 'room', 37.4, -121.9, ?, '2026-01-01T00:00:00Z', 5)`, twoDaysAgo)
 
 	// Seed transmissions
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
-		VALUES ('AABB', 'abc123def4567890', ?, 1, 4, '{"pubKey":"aabbccdd11223344","name":"TestRepeater","type":"ADVERT","timestamp":1700000000,"timestampISO":"2023-11-14T22:13:20.000Z","signature":"abcdef","flags":{"isRepeater":true},"lat":37.5,"lon":-122.0}')`, recent)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
-		VALUES ('CCDD', '1234567890abcdef', ?, 1, 5, '{"type":"CHAN","channel":"#test","text":"Hello: World","sender":"TestUser"}')`, yesterday)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('AABB', 'abc123def4567890', ?, 1, 4, '{"pubKey":"aabbccdd11223344","name":"TestRepeater","type":"ADVERT","timestamp":1700000000,"timestampISO":"2023-11-14T22:13:20.000Z","signature":"abcdef","flags":{"isRepeater":true},"lat":37.5,"lon":-122.0}', '#test')`, recent)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('CCDD', '1234567890abcdef', ?, 1, 5, '{"type":"CHAN","channel":"#test","text":"Hello: World","sender":"TestUser"}', '#test')`, yesterday)
 	// Second ADVERT for same node with different hash_size (raw_hex byte 0x1F → hs=1 vs 0xBB → hs=3)
 	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
 		VALUES ('AA1F', 'def456abc1230099', ?, 1, 4, '{"pubKey":"aabbccdd11223344","name":"TestRepeater","type":"ADVERT","timestamp":1700000100,"timestampISO":"2023-11-14T22:14:40.000Z","signature":"fedcba","flags":{"isRepeater":true},"lat":37.5,"lon":-122.0}')`, yesterday)
@@ -735,12 +736,12 @@ func TestGetChannelMessagesRegionFiltering(t *testing.T) {
 
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs1', 'Observer One', 'SJC')`)
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs2', 'Observer Two', ' sfo ')`)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('AA', 'chanregion0001', ?, 1, 5,
-		'{"type":"CHAN","channel":"#region","text":"SjcUser: One","sender":"SjcUser"}')`, ts1)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		'{"type":"CHAN","channel":"#region","text":"SjcUser: One","sender":"SjcUser"}', '#region')`, ts1)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('BB', 'chanregion0002', ?, 1, 5,
-		'{"type":"CHAN","channel":"#region","text":"SfoUser: Two","sender":"SfoUser"}')`, ts2)
+		'{"type":"CHAN","channel":"#region","text":"SfoUser: Two","sender":"SfoUser"}', '#region')`, ts2)
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
 		VALUES (1, 1, 10.0, -90, '[]', ?)`, epoch1)
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
@@ -1119,6 +1120,7 @@ func setupTestDBV2(t *testing.T) *DB {
 			payload_type INTEGER,
 			payload_version INTEGER,
 			decoded_json TEXT,
+			channel_hash TEXT DEFAULT NULL,
 			created_at TEXT DEFAULT (datetime('now'))
 		);
 
@@ -1202,12 +1204,12 @@ func TestGetChannelMessagesDedup(t *testing.T) {
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs2', 'Observer Two', 'SFO')`)
 
 	// Insert two transmissions with same hash to test dedup
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('AA', 'chanmsg00000001', '2026-01-15T10:00:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#general","text":"User1: Hello","sender":"User1"}')`)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		'{"type":"CHAN","channel":"#general","text":"User1: Hello","sender":"User1"}', '#general')`)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('BB', 'chanmsg00000002', '2026-01-15T10:01:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#general","text":"User2: World","sender":"User2"}')`)
+		'{"type":"CHAN","channel":"#general","text":"User2: World","sender":"User2"}', '#general')`)
 
 	// Observations: first msg seen by two observers (dedup), second by one
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
@@ -1251,9 +1253,9 @@ func TestGetChannelMessagesNoSender(t *testing.T) {
 	defer db.Close()
 
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs1', 'Observer One', 'SJC')`)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('CC', 'chanmsg00000003', '2026-01-15T10:02:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#noname","text":"plain text no colon"}')`)
+		'{"type":"CHAN","channel":"#noname","text":"plain text no colon"}', '#noname')`)
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
 		VALUES (1, 1, 12.0, -90, null, 1736935300)`)
 
@@ -1356,9 +1358,9 @@ func TestGetChannelMessagesObserverFallback(t *testing.T) {
 	defer db.Close()
 
 	// Observer with ID but no name entry (observer_idx won't match)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('AA', 'chanmsg00000004', '2026-01-15T10:00:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#obs","text":"Sender: Test","sender":"Sender"}')`)
+		'{"type":"CHAN","channel":"#obs","text":"Sender: Test","sender":"Sender"}', '#obs')`)
 	// Observation without observer (observer_idx = NULL)
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
 		VALUES (1, NULL, 12.0, -90, null, 1736935200)`)
@@ -1380,12 +1382,12 @@ func TestGetChannelsMultiple(t *testing.T) {
 	defer db.Close()
 
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs1', 'Observer', 'SJC')`)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('AA', 'chan1hash', '2026-01-15T10:00:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#alpha","text":"Alice: Hello","sender":"Alice"}')`)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		'{"type":"CHAN","channel":"#alpha","text":"Alice: Hello","sender":"Alice"}', '#alpha')`)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('BB', 'chan2hash', '2026-01-15T10:01:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#beta","text":"Bob: World","sender":"Bob"}')`)
+		'{"type":"CHAN","channel":"#beta","text":"Bob: World","sender":"Bob"}', '#beta')`)
 	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
 		VALUES ('CC', 'chan3hash', '2026-01-15T10:02:00Z', 1, 5,
 		'{"type":"CHAN","channel":"","text":"No channel"}')`)
@@ -1468,13 +1470,13 @@ func TestGetChannelsStaleMessage(t *testing.T) {
 	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs2', 'Observer2', 'SFO')`)
 
 	// Older message (first_seen T1)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('AA', 'oldhash1', '2026-01-15T10:00:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#test","text":"Alice: Old message","sender":"Alice"}')`)
+		'{"type":"CHAN","channel":"#test","text":"Alice: Old message","sender":"Alice"}', '#test')`)
 	// Newer message (first_seen T2 > T1)
-	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
 		VALUES ('BB', 'newhash2', '2026-01-15T10:05:00Z', 1, 5,
-		'{"type":"CHAN","channel":"#test","text":"Bob: New message","sender":"Bob"}')`)
+		'{"type":"CHAN","channel":"#test","text":"Bob: New message","sender":"Bob"}', '#test')`)
 
 	// Observations: older message re-observed AFTER newer message (stale scenario)
 	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, timestamp)
@@ -1504,6 +1506,61 @@ func TestGetChannelsStaleMessage(t *testing.T) {
 	}
 }
 
+func TestGetChannelsRegionFiltering(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+
+	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs1', 'Observer1', 'SJC')`)
+	db.conn.Exec(`INSERT INTO observers (id, name, iata) VALUES ('obs2', 'Observer2', 'SFO')`)
+
+	// Channel message seen only in SJC
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('AA', 'hash1', '2026-01-15T10:00:00Z', 1, 5,
+		'{"type":"CHAN","channel":"#sjc-only","text":"Alice: Hello SJC","sender":"Alice"}', '#sjc-only')`)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, timestamp)
+		VALUES (1, 1, 12.0, -90, 1736935200)`)
+
+	// Channel message seen only in SFO
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('BB', 'hash2', '2026-01-15T10:05:00Z', 1, 5,
+		'{"type":"CHAN","channel":"#sfo-only","text":"Bob: Hello SFO","sender":"Bob"}', '#sfo-only')`)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, timestamp)
+		VALUES (2, 2, 14.0, -88, 1736935500)`)
+
+	// No region filter — both channels
+	all, err := db.GetChannels()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(all) != 2 {
+		t.Fatalf("expected 2 channels without region filter, got %d", len(all))
+	}
+
+	// Filter SJC — only #sjc-only
+	sjc, err := db.GetChannels("SJC")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(sjc) != 1 {
+		t.Fatalf("expected 1 channel for SJC, got %d", len(sjc))
+	}
+	if sjc[0]["name"] != "#sjc-only" {
+		t.Errorf("expected channel '#sjc-only', got %q", sjc[0]["name"])
+	}
+
+	// Filter SFO — only #sfo-only
+	sfo, err := db.GetChannels("SFO")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(sfo) != 1 {
+		t.Fatalf("expected 1 channel for SFO, got %d", len(sfo))
+	}
+	if sfo[0]["name"] != "#sfo-only" {
+		t.Errorf("expected channel '#sfo-only', got %q", sfo[0]["name"])
+	}
+}
+
 func TestNodeTelemetryFields(t *testing.T) {
 	db := setupTestDB(t)
 	defer db.Close()

cmd/server/decoder.go

@@ -116,6 +116,7 @@ type DecodedPacket struct {
 	Path           Path            `json:"path"`
 	Payload        Payload         `json:"payload"`
 	Raw            string          `json:"raw"`
+	Anomaly        string          `json:"anomaly,omitempty"`
 }
 
 func decodeHeader(b byte) Header {
@@ -388,22 +389,34 @@ func DecodePacket(hexString string, validateSignatures bool) (*DecodedPacket, er
 	payload := decodePayload(header.PayloadType, payloadBuf, validateSignatures)
 
 	// TRACE packets store hop IDs in the payload (buf[9:]) rather than the header
-	// path field. The header path byte still encodes hashSize in bits 6-7, which
-	// we use to split the payload path data into individual hop prefixes.
-	// The header path contains SNR bytes — one per hop that actually forwarded.
+	// path field. Firmware always sends TRACE as DIRECT (route_type 2 or 3);
+	// FLOOD-routed TRACEs are anomalous but handled gracefully (parsed, but
+	// flagged). The TRACE flags byte (payload offset 8) encodes path_sz in
+	// bits 0-1 as a power-of-two exponent: hash_bytes = 1 << path_sz.
+	// NOT the header path byte's hash_size bits. The header path contains SNR
+	// bytes — one per hop that actually forwarded.
 	// We expose hopsCompleted (count of SNR bytes) so consumers can distinguish
 	// how far the trace got vs the full intended route.
+	var anomaly string
 	if header.PayloadType == PayloadTRACE && payload.PathData != "" {
+		// Flag anomalous routing — firmware only sends TRACE as DIRECT
+		if header.RouteType != RouteDirect && header.RouteType != RouteTransportDirect {
+			anomaly = "TRACE packet with non-DIRECT routing (expected DIRECT or TRANSPORT_DIRECT)"
+		}
 		// The header path hops count represents SNR entries = completed hops
 		hopsCompleted := path.HashCount
 		pathBytes, err := hex.DecodeString(payload.PathData)
-		if err == nil && path.HashSize > 0 {
-			hops := make([]string, 0, len(pathBytes)/path.HashSize)
-			for i := 0; i+path.HashSize <= len(pathBytes); i += path.HashSize {
-				hops = append(hops, strings.ToUpper(hex.EncodeToString(pathBytes[i:i+path.HashSize])))
+		if err == nil && payload.TraceFlags != nil {
+			// path_sz from flags byte is a power-of-two exponent per firmware:
+			// hash_bytes = 1 << (flags & 0x03)
+			pathSz := 1 << (*payload.TraceFlags & 0x03)
+			hops := make([]string, 0, len(pathBytes)/pathSz)
+			for i := 0; i+pathSz <= len(pathBytes); i += pathSz {
+				hops = append(hops, strings.ToUpper(hex.EncodeToString(pathBytes[i:i+pathSz])))
 			}
 			path.Hops = hops
 			path.HashCount = len(hops)
+			path.HashSize = pathSz
 			path.HopsCompleted = &hopsCompleted
 		}
 	}
@@ -424,6 +437,7 @@ func DecodePacket(hexString string, validateSignatures bool) (*DecodedPacket, er
 		Path:           path,
 		Payload:        payload,
 		Raw:            strings.ToUpper(hexString),
+		Anomaly:        anomaly,
 	}, nil
 }
 
@@ -528,6 +542,9 @@ func BuildBreakdown(hexString string) *Breakdown {
 }
 
 // ComputeContentHash computes the SHA-256-based content hash (first 16 hex chars).
+// It hashes the payload-type nibble + payload (skipping path bytes) to produce a
+// route-independent identifier for the same logical packet. For TRACE packets,
+// path_len is included in the hash to match firmware behavior.
 func ComputeContentHash(rawHex string) string {
 	buf, err := hex.DecodeString(rawHex)
 	if err != nil || len(buf) < 2 {
@@ -563,7 +580,18 @@ func ComputeContentHash(rawHex string) string {
 	}
 
 	payload := buf[payloadStart:]
-	toHash := append([]byte{headerByte}, payload...)
+
+	// Hash payload-type byte only (bits 2-5 of header), not the full header.
+	// Firmware: SHA256(payload_type + [path_len for TRACE] + payload)
+	// Using the full header caused different hashes for the same logical packet
+	// when route type or version bits differed. See issue #786.
+	payloadType := (headerByte >> 2) & 0x0F
+	toHash := []byte{payloadType}
+	if int(payloadType) == PayloadTRACE {
+		// Firmware uses uint16_t path_len (2 bytes, little-endian)
+		toHash = append(toHash, pathByte, 0x00)
+	}
+	toHash = append(toHash, payload...)
 
 	h := sha256.Sum256(toHash)
 	return hex.EncodeToString(h[:])[:16]

cmd/server/decoder_test.go

@@ -357,6 +357,10 @@ func TestDecodePacket_TraceHopsCompleted(t *testing.T) {
 	if *pkt.Path.HopsCompleted != 2 {
 		t.Errorf("expected HopsCompleted=2, got %d", *pkt.Path.HopsCompleted)
 	}
+	// FLOOD routing for TRACE is anomalous
+	if pkt.Anomaly == "" {
+		t.Error("expected anomaly flag for FLOOD-routed TRACE")
+	}
 }
 
 func TestDecodePacket_TraceNoSNR(t *testing.T) {
@@ -407,6 +411,124 @@ func TestDecodePacket_TraceFullyCompleted(t *testing.T) {
 	}
 }
 
+func TestDecodePacket_TraceFlags1_TwoBytePathSz(t *testing.T) {
+	// TRACE with flags=1 → path_sz = 1 << (1 & 0x03) = 2-byte hashes
+	// Firmware always sends TRACE as DIRECT (route_type=2), so header byte =
+	// (0<<6)|(9<<2)|2 = 0x26. path_length 0x00 = 0 SNR bytes.
+	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
+		"01000000" + // tag
+		"02000000" + // authCode
+		"01" + // flags = 1 → path_sz = 2
+		"AABBCCDD" // 4 bytes = 2 hops of 2-byte each
+
+	pkt, err := DecodePacket(hex, false)
+	if err != nil {
+		t.Fatalf("DecodePacket error: %v", err)
+	}
+	if len(pkt.Path.Hops) != 2 {
+		t.Errorf("expected 2 hops (2-byte path_sz), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
+	}
+	if pkt.Path.HashSize != 2 {
+		t.Errorf("expected HashSize=2, got %d", pkt.Path.HashSize)
+	}
+	if pkt.Anomaly != "" {
+		t.Errorf("expected no anomaly for DIRECT TRACE, got %q", pkt.Anomaly)
+	}
+}
+
+func TestDecodePacket_TraceFlags2_FourBytePathSz(t *testing.T) {
+	// TRACE with flags=2 → path_sz = 1 << (2 & 0x03) = 4-byte hashes
+	// DIRECT route_type (0x26)
+	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
+		"01000000" + // tag
+		"02000000" + // authCode
+		"02" + // flags = 2 → path_sz = 4
+		"AABBCCDD11223344" // 8 bytes = 2 hops of 4-byte each
+
+	pkt, err := DecodePacket(hex, false)
+	if err != nil {
+		t.Fatalf("DecodePacket error: %v", err)
+	}
+	if len(pkt.Path.Hops) != 2 {
+		t.Errorf("expected 2 hops (4-byte path_sz), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
+	}
+	if pkt.Path.HashSize != 4 {
+		t.Errorf("expected HashSize=4, got %d", pkt.Path.HashSize)
+	}
+}
+
+func TestDecodePacket_TracePathSzUnevenPayload(t *testing.T) {
+	// TRACE with flags=1 → path_sz=2, but 5 bytes of path data (not evenly divisible)
+	// Should produce 2 hops (4 bytes) and ignore the trailing byte
+	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
+		"01000000" + // tag
+		"02000000" + // authCode
+		"01" + // flags = 1 → path_sz = 2
+		"AABBCCDDEE" // 5 bytes → 2 hops, 1 byte remainder ignored
+
+	pkt, err := DecodePacket(hex, false)
+	if err != nil {
+		t.Fatalf("DecodePacket error: %v", err)
+	}
+	if len(pkt.Path.Hops) != 2 {
+		t.Errorf("expected 2 hops (trailing byte ignored), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
+	}
+}
+
+func TestDecodePacket_TraceTransportDirect(t *testing.T) {
+	// TRACE via TRANSPORT_DIRECT (route_type=3) — includes 4 transport code bytes
+	// header: (0<<6)|(9<<2)|3 = 0x27
+	hex := "27" + // header (TRANSPORT_DIRECT+TRACE)
+		"AABB" + "CCDD" + // transport codes (2+2 bytes)
+		"02" + // path_length: hash_count=2 SNR bytes
+		"EEFF" + // 2 SNR bytes
+		"01000000" + // tag
+		"02000000" + // authCode
+		"00" + // flags = 0 → path_sz = 1
+		"112233" // 3 hops (1-byte each)
+
+	pkt, err := DecodePacket(hex, false)
+	if err != nil {
+		t.Fatalf("DecodePacket error: %v", err)
+	}
+	if pkt.TransportCodes == nil {
+		t.Fatal("expected transport codes for TRANSPORT_DIRECT")
+	}
+	if pkt.TransportCodes.Code1 != "AABB" {
+		t.Errorf("expected Code1=AABB, got %s", pkt.TransportCodes.Code1)
+	}
+	if len(pkt.Path.Hops) != 3 {
+		t.Errorf("expected 3 hops, got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
+	}
+	if pkt.Path.HopsCompleted == nil || *pkt.Path.HopsCompleted != 2 {
+		t.Errorf("expected HopsCompleted=2, got %v", pkt.Path.HopsCompleted)
+	}
+	if pkt.Anomaly != "" {
+		t.Errorf("expected no anomaly for TRANSPORT_DIRECT TRACE, got %q", pkt.Anomaly)
+	}
+}
+
+func TestDecodePacket_TraceFloodRouteAnomaly(t *testing.T) {
+	// TRACE via FLOOD (route_type=1) — anomalous per firmware (firmware only
+	// sends TRACE as DIRECT). Should still parse but flag the anomaly.
+	hex := "2500" + // header (FLOOD+TRACE) + path_length (0 SNR)
+		"01000000" + // tag
+		"02000000" + // authCode
+		"01" + // flags = 1 → path_sz = 2
+		"AABBCCDD" // 4 bytes = 2 hops of 2-byte each
+
+	pkt, err := DecodePacket(hex, false)
+	if err != nil {
+		t.Fatalf("should not crash on anomalous FLOOD+TRACE: %v", err)
+	}
+	if len(pkt.Path.Hops) != 2 {
+		t.Errorf("expected 2 hops even for anomalous FLOOD route, got %d", len(pkt.Path.Hops))
+	}
+	if pkt.Anomaly == "" {
+		t.Error("expected anomaly flag for FLOOD-routed TRACE, got empty string")
+	}
+}
+
 func TestDecodeAdvertSignatureValidation(t *testing.T) {
 	pub, priv, err := ed25519.GenerateKey(nil)
 	if err != nil {

cmd/server/encrypted_channels_test.go

@@ -0,0 +1,145 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+// seedEncryptedChannelData adds undecryptable GRP_TXT packets to the test DB.
+func seedEncryptedChannelData(t *testing.T, db *DB) {
+	t.Helper()
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+
+	// Two encrypted GRP_TXT packets on channel hash "A1B2"
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('EE01', 'enc_hash_001', ?, 1, 5, '{"type":"GRP_TXT","channelHashHex":"A1B2","decryptionStatus":"no_key"}', 'enc_A1B2')`, recent)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json, channel_hash)
+		VALUES ('EE02', 'enc_hash_002', ?, 1, 5, '{"type":"GRP_TXT","channelHashHex":"A1B2","decryptionStatus":"no_key"}', 'enc_A1B2')`, recent)
+
+	// Observations for both
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES ((SELECT id FROM transmissions WHERE hash='enc_hash_001'), 1, 10.0, -90, '[]', ?)`, recentEpoch)
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES ((SELECT id FROM transmissions WHERE hash='enc_hash_002'), 1, 10.0, -90, '[]', ?)`, recentEpoch)
+}
+
+func TestGetEncryptedChannels(t *testing.T) {
+	db := setupTestDB(t)
+	defer db.Close()
+	seedTestData(t, db)
+	seedEncryptedChannelData(t, db)
+
+	channels, err := db.GetEncryptedChannels()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(channels) != 1 {
+		t.Fatalf("expected 1 encrypted channel, got %d", len(channels))
+	}
+	ch := channels[0]
+	if ch["hash"] != "enc_A1B2" {
+		t.Errorf("expected hash enc_A1B2, got %v", ch["hash"])
+	}
+	if ch["encrypted"] != true {
+		t.Errorf("expected encrypted=true, got %v", ch["encrypted"])
+	}
+	if ch["messageCount"] != 2 {
+		t.Errorf("expected messageCount=2, got %v", ch["messageCount"])
+	}
+}
+
+func TestChannelsAPIExcludesEncrypted(t *testing.T) {
+	_, router := setupTestServer(t)
+	// Seed encrypted data into the server's DB
+	// setupTestServer uses seedTestData which has no encrypted packets,
+	// so default /api/channels should NOT include encrypted channels.
+	req := httptest.NewRequest("GET", "/api/channels", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	var body map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &body)
+	channels := body["channels"].([]interface{})
+
+	for _, ch := range channels {
+		m := ch.(map[string]interface{})
+		if enc, ok := m["encrypted"]; ok && enc == true {
+			t.Errorf("default /api/channels should not include encrypted channels, found: %v", m["hash"])
+		}
+	}
+}
+
+func TestChannelsAPIIncludesEncryptedWithParam(t *testing.T) {
+	srv, router := setupTestServer(t)
+	// Add encrypted data to the server's DB
+	seedEncryptedChannelData(t, srv.db)
+	// Reload store so in-memory also has the data
+	store := NewPacketStore(srv.db, nil)
+	if err := store.Load(); err != nil {
+		t.Fatalf("store.Load: %v", err)
+	}
+	srv.store = store
+
+	req := httptest.NewRequest("GET", "/api/channels?includeEncrypted=true", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	var body map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &body)
+	channels := body["channels"].([]interface{})
+
+	foundEncrypted := false
+	for _, ch := range channels {
+		m := ch.(map[string]interface{})
+		if enc, ok := m["encrypted"]; ok && enc == true {
+			foundEncrypted = true
+			break
+		}
+	}
+	if !foundEncrypted {
+		t.Error("expected encrypted channels with includeEncrypted=true, found none")
+	}
+}
+
+func TestChannelMessagesExcludesEncrypted(t *testing.T) {
+	srv, router := setupTestServer(t)
+	seedEncryptedChannelData(t, srv.db)
+	store := NewPacketStore(srv.db, nil)
+	if err := store.Load(); err != nil {
+		t.Fatalf("store.Load: %v", err)
+	}
+	srv.store = store
+
+	// Request messages for the encrypted channel — should return empty
+	req := httptest.NewRequest("GET", "/api/channels/enc_A1B2/messages", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	var body map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &body)
+	messages, ok := body["messages"].([]interface{})
+	if !ok {
+		// messages might be null/missing — that's fine, means no messages
+		return
+	}
+	// Encrypted messages should not be returned as readable messages
+	for _, msg := range messages {
+		m := msg.(map[string]interface{})
+		if text, ok := m["text"].(string); ok && text != "" {
+			t.Errorf("encrypted channel should not return readable messages, got text: %s", text)
+		}
+	}
+}

cmd/server/eviction_test.go

@@ -247,6 +247,11 @@ func TestEvictStale_CleansNodeIndexes(t *testing.T) {
 
 func TestEvictStale_CleansResolvedPathNodeIndexes(t *testing.T) {
 	now := time.Now().UTC()
+
+	// Create a temp DB for on-demand SQL fetch during eviction
+	db := setupTestDB(t)
+	defer db.Close()
+
 	store := &PacketStore{
 		packets:       make([]*StoreTx, 0),
 		byHash:        make(map[string]*StoreTx),
@@ -267,25 +272,33 @@ func TestEvictStale_CleansResolvedPathNodeIndexes(t *testing.T) {
 		subpathCache:  make(map[string]*cachedResult),
 		rfCacheTTL:    15 * time.Second,
 		retentionHours: 24,
+		db:             db,
+		useResolvedPathIndex: true,
 	}
+	store.initResolvedPathIndex()
 
-	// Create a packet indexed only via resolved_path (no decoded JSON pubkeys)
+	// Create a packet indexed via resolved_path pubkeys
 	relayPK := "relay0001abcdef"
+	txID := 1
+	obsID := 100
 	tx := &StoreTx{
-		ID:        1,
+		ID:        txID,
 		Hash:      "hash_rp_001",
 		FirstSeen: now.Add(-48 * time.Hour).UTC().Format(time.RFC3339),
 	}
-	rpPtr := &relayPK
 	obs := &StoreObs{
-		ID:             100,
-		TransmissionID: 1,
+		ID:             obsID,
+		TransmissionID: txID,
 		ObserverID:     "obs0",
 		Timestamp:      tx.FirstSeen,
-		ResolvedPath:   []*string{rpPtr},
 	}
 	tx.Observations = append(tx.Observations, obs)
-	tx.ResolvedPath = []*string{rpPtr}
+
+	// Insert into DB so on-demand SQL fetch works during eviction
+	db.conn.Exec("INSERT INTO transmissions (id, raw_hex, hash, first_seen) VALUES (?, '', ?, ?)",
+		txID, tx.Hash, tx.FirstSeen)
+	db.conn.Exec("INSERT INTO observations (id, transmission_id, observer_idx, path_json, timestamp, resolved_path) VALUES (?, ?, 1, ?, ?, ?)",
+		obsID, txID, `["aa"]`, now.Add(-48*time.Hour).Unix(), `["`+relayPK+`"]`)
 
 	store.packets = append(store.packets, tx)
 	store.byHash[tx.Hash] = tx
@@ -293,8 +306,9 @@ func TestEvictStale_CleansResolvedPathNodeIndexes(t *testing.T) {
 	store.byObsID[obs.ID] = obs
 	store.byObserver["obs0"] = append(store.byObserver["obs0"], obs)
 
-	// Index via resolved_path
-	store.indexByNode(tx)
+	// Index relay via decode-window simulation
+	store.addToByNode(tx, relayPK)
+	store.addToResolvedPubkeyIndex(txID, []string{relayPK})
 
 	// Verify indexed
 	if len(store.byNode[relayPK]) != 1 {
@@ -304,7 +318,7 @@ func TestEvictStale_CleansResolvedPathNodeIndexes(t *testing.T) {
 		t.Fatalf("expected nodeHashes[%s] to contain %s", relayPK, tx.Hash)
 	}
 
-	evicted := store.EvictStale()
+	evicted := store.RunEviction()
 	if evicted != 1 {
 		t.Fatalf("expected 1 evicted, got %d", evicted)
 	}
@@ -316,6 +330,14 @@ func TestEvictStale_CleansResolvedPathNodeIndexes(t *testing.T) {
 	if _, exists := store.nodeHashes[relayPK]; exists {
 		t.Fatalf("expected nodeHashes[%s] to be deleted after eviction", relayPK)
 	}
+	// Verify resolved pubkey index is cleaned up
+	h := resolvedPubkeyHash(relayPK)
+	if len(store.resolvedPubkeyIndex[h]) != 0 {
+		t.Fatalf("expected resolvedPubkeyIndex to be empty after eviction")
+	}
+	if _, exists := store.resolvedPubkeyReverse[txID]; exists {
+		t.Fatalf("expected resolvedPubkeyReverse to be empty after eviction")
+	}
 }
 
 func TestEvictStale_RunEvictionThreadSafe(t *testing.T) {
@@ -541,13 +563,19 @@ func TestEstimateStoreTxBytes(t *testing.T) {
 		PathJSON:    `["aa","bb"]`,
 	}
 	est := estimateStoreTxBytes(tx)
-	// Verify the function returns a reasonable value matching our manual calculation
+	// Manual calculation: base + string lengths + index entries + perTxMaps + path hops + subpaths
+	hops := int64(len(txGetParsedPath(tx)))
 	manualCalc := int64(storeTxBaseBytes) + int64(len(tx.RawHex)+len(tx.Hash)+len(tx.DecodedJSON)+len(tx.PathJSON)) + int64(numIndexesPerTx*indexEntryBytes)
+	manualCalc += perTxMapsBytes
+	manualCalc += hops * perPathHopBytes
+	if hops > 1 {
+		manualCalc += (hops * (hops - 1) / 2) * perSubpathEntryBytes
+	}
 	if est != manualCalc {
 		t.Fatalf("estimateStoreTxBytes = %d, want %d (manual calc)", est, manualCalc)
 	}
-	if est < 600 || est > 800 {
-		t.Fatalf("estimateStoreTxBytes = %d, expected in range [600, 800]", est)
+	if est < 600 || est > 1200 {
+		t.Fatalf("estimateStoreTxBytes = %d, expected in range [600, 1200]", est)
 	}
 }
 

cmd/server/hash_migrate.go

@@ -0,0 +1,119 @@
+package main
+
+import (
+	"log"
+	"time"
+)
+
+// migrateContentHashesAsync recomputes content hashes in batches after the
+// server is already serving HTTP.  Packets whose hash changes are updated in
+// both the DB and the in-memory byHash index.  The migration is idempotent:
+// once all hashes match the current formula it completes instantly.
+func migrateContentHashesAsync(store *PacketStore, batchSize int, yieldDuration time.Duration) {
+	defer func() {
+		if r := recover(); r != nil {
+			log.Printf("[hash-migrate] panic recovered: %v", r)
+		}
+		store.hashMigrationComplete.Store(true)
+	}()
+
+	// Snapshot the packet slice length under lock (packets only grow).
+	store.mu.RLock()
+	total := len(store.packets)
+	store.mu.RUnlock()
+
+	migrated := 0
+	for offset := 0; offset < total; offset += batchSize {
+		end := offset + batchSize
+		if end > total {
+			end = total
+		}
+
+		// Collect stale hashes in this batch under RLock.
+		type hashUpdate struct {
+			tx      *StoreTx
+			oldHash string
+			newHash string
+		}
+		var updates []hashUpdate
+
+		store.mu.RLock()
+		for _, tx := range store.packets[offset:end] {
+			if tx.RawHex == "" {
+				continue
+			}
+			newHash := ComputeContentHash(tx.RawHex)
+			if newHash != tx.Hash {
+				updates = append(updates, hashUpdate{tx: tx, oldHash: tx.Hash, newHash: newHash})
+			}
+		}
+		store.mu.RUnlock()
+
+		if len(updates) == 0 {
+			continue
+		}
+
+		// Write batch to DB in a single transaction.
+		dbTx, err := store.db.conn.Begin()
+		if err != nil {
+			log.Printf("[hash-migrate] begin tx: %v", err)
+			continue
+		}
+		stmt, err := dbTx.Prepare("UPDATE transmissions SET hash = ? WHERE id = ?")
+		if err != nil {
+			log.Printf("[hash-migrate] prepare: %v", err)
+			dbTx.Rollback()
+			continue
+		}
+
+		for _, u := range updates {
+			if _, err := stmt.Exec(u.newHash, u.tx.ID); err != nil {
+				// UNIQUE constraint = two old hashes map to the same new hash (duplicate).
+				// Merge observations to the surviving tx, delete the duplicate.
+				log.Printf("[hash-migrate] tx %d collides — merging duplicate", u.tx.ID)
+				var survID int
+				if err2 := dbTx.QueryRow("SELECT id FROM transmissions WHERE hash = ?", u.newHash).Scan(&survID); err2 == nil {
+					dbTx.Exec("UPDATE observations SET transmission_id = ? WHERE transmission_id = ?", survID, u.tx.ID)
+					dbTx.Exec("DELETE FROM transmissions WHERE id = ?", u.tx.ID)
+					u.newHash = "" // mark for in-memory removal only
+				}
+			}
+		}
+		stmt.Close()
+
+		if err := dbTx.Commit(); err != nil {
+			log.Printf("[hash-migrate] commit: %v", err)
+			continue
+		}
+
+		// Update in-memory index under write lock.
+		store.mu.Lock()
+		for _, u := range updates {
+			delete(store.byHash, u.oldHash)
+			if u.newHash == "" {
+				// Merged duplicate — remove from packets slice and indexes.
+				delete(store.byTxID, u.tx.ID)
+				// Move observations to survivor if present.
+				if surv := store.byHash[ComputeContentHash(u.tx.RawHex)]; surv != nil {
+					for _, obs := range u.tx.Observations {
+						surv.Observations = append(surv.Observations, obs)
+						surv.ObservationCount++
+					}
+				}
+			} else {
+				u.tx.Hash = u.newHash
+				store.byHash[u.newHash] = u.tx
+			}
+		}
+		store.mu.Unlock()
+
+		migrated += len(updates)
+
+		// Yield to let HTTP handlers run.
+		time.Sleep(yieldDuration)
+	}
+
+	if migrated > 0 {
+		log.Printf("[hash-migrate] Migrated %d content hashes to new formula", migrated)
+	}
+}

cmd/server/hash_migrate_test.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"testing"
+	"time"
+)
+
+func TestMigrateContentHashesAsync(t *testing.T) {
+	db := setupTestDBv2(t)
+	store := NewPacketStore(db, nil)
+
+	// Insert a packet with a manually wrong hash (simulating old formula).
+	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
+	correctHash := ComputeContentHash(rawHex)
+	wrongHash := "deadbeef12345678"
+
+	_, err := db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type)
+		VALUES (?, ?, datetime('now'), 0, 2)`, rawHex, wrongHash)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := store.Load(); err != nil {
+		t.Fatal(err)
+	}
+
+	if store.byHash[wrongHash] == nil {
+		t.Fatal("expected packet under wrong hash before migration")
+	}
+
+	migrateContentHashesAsync(store, 100, time.Millisecond)
+
+	if !store.hashMigrationComplete.Load() {
+		t.Error("expected hashMigrationComplete to be true")
+	}
+	if store.byHash[wrongHash] != nil {
+		t.Error("old hash should be removed from index")
+	}
+	if store.byHash[correctHash] == nil {
+		t.Error("new hash should be in index")
+	}
+
+	var dbHash string
+	err = db.conn.QueryRow("SELECT hash FROM transmissions WHERE raw_hex = ?", rawHex).Scan(&dbHash)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if dbHash != correctHash {
+		t.Errorf("DB hash = %s, want %s", dbHash, correctHash)
+	}
+}
+
+func TestMigrateContentHashesAsync_NoOp(t *testing.T) {
+	db := setupTestDBv2(t)
+	store := NewPacketStore(db, nil)
+
+	rawHex := "0A00D69FD7A5A7475DB07337749AE61FA53A4788E976"
+	correctHash := ComputeContentHash(rawHex)
+
+	_, err := db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type)
+		VALUES (?, ?, datetime('now'), 0, 2)`, rawHex, correctHash)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if err := store.Load(); err != nil {
+		t.Fatal(err)
+	}
+
+	migrateContentHashesAsync(store, 100, time.Millisecond)
+
+	if !store.hashMigrationComplete.Load() {
+		t.Error("expected hashMigrationComplete to be true")
+	}
+	if store.byHash[correctHash] == nil {
+		t.Error("hash should remain in index")
+	}
+}

cmd/server/issue673_test.go

@@ -0,0 +1,107 @@
+package main
+
+import (
+	"encoding/json"
+	"testing"
+	"time"
+
+	_ "modernc.org/sqlite"
+)
+
+const issue673NodePK = "7502f19f44cad6d7b626e1d811c00a914af452636182ccded3fd019803395ec9"
+
+// setupIssue673Store builds an in-memory store with one repeater node having:
+//   - one ADVERT packet (legitimately indexed in byNode)
+//   - one GRP_TXT packet whose decoded text contains the node's pubkey (false-positive candidate)
+func setupIssue673Store(t *testing.T) (*PacketStore, *DB) {
+	t.Helper()
+	db := setupTestDB(t)
+
+	_, err := db.conn.Exec(
+		"INSERT INTO nodes (public_key, name, role) VALUES (?, ?, ?)",
+		issue673NodePK, "Quail Hollow Park", "repeater",
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	ps := NewPacketStore(db, nil)
+	now := time.Now().UTC().Format(time.RFC3339)
+
+	pt4 := 4 // ADVERT
+	pt5 := 5 // GRP_TXT
+
+	advertDecoded, _ := json.Marshal(map[string]interface{}{"pubKey": issue673NodePK})
+	advert := &StoreTx{
+		ID:          1,
+		Hash:        "advert_hash_673",
+		PayloadType: &pt4,
+		DecodedJSON: string(advertDecoded),
+		FirstSeen:   now,
+	}
+
+	otherPK := "aabbccddaabbccddaabbccddaabbccddaabbccddaabbccddaabbccddaabbccdd"
+	chatDecoded, _ := json.Marshal(map[string]interface{}{
+		"srcPubKey": otherPK,
+		"text":      "Check out node " + issue673NodePK + " on the analyzer",
+	})
+	chat := &StoreTx{
+		ID:          2,
+		Hash:        "chat_hash_673",
+		PayloadType: &pt5,
+		DecodedJSON: string(chatDecoded),
+		FirstSeen:   now,
+	}
+
+	ps.mu.Lock()
+	ps.packets = append(ps.packets, advert, chat)
+	ps.byHash[advert.Hash] = advert
+	ps.byHash[chat.Hash] = chat
+	ps.byTxID[advert.ID] = advert
+	ps.byTxID[chat.ID] = chat
+	ps.byNode[issue673NodePK] = []*StoreTx{advert}
+	ps.mu.Unlock()
+
+	return ps, db
+}
+
+// TestGetNodeAnalytics_ExcludesGRPTXTWithPubkeyInText verifies that a GRP_TXT packet
+// whose message text contains a node's pubkey is not counted in that node's analytics.
+func TestGetNodeAnalytics_ExcludesGRPTXTWithPubkeyInText(t *testing.T) {
+	ps, db := setupIssue673Store(t)
+	defer db.Close()
+
+	analytics, err := ps.GetNodeAnalytics(issue673NodePK, 30)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if analytics == nil {
+		t.Fatal("expected analytics, got nil")
+	}
+
+	for _, ptc := range analytics.PacketTypeBreakdown {
+		if ptc.PayloadType == 5 {
+			t.Errorf("GRP_TXT (type 5) should not appear in analytics for repeater node, got count=%d", ptc.Count)
+		}
+	}
+}
+
+// TestFilterPackets_NodeQueryDoesNotMatchChatText verifies that the slow path of
+// filterPackets (node filter combined with Since) does not return a GRP_TXT packet
+// whose pubkey appears only in message text, not in a structured pubkey field.
+func TestFilterPackets_NodeQueryDoesNotMatchChatText(t *testing.T) {
+	ps, db := setupIssue673Store(t)
+	defer db.Close()
+
+	yesterday := time.Now().Add(-24 * time.Hour).UTC().Format(time.RFC3339)
+	result := ps.QueryPackets(PacketQuery{Node: issue673NodePK, Since: yesterday, Limit: 50})
+
+	if result.Total != 1 {
+		t.Errorf("expected 1 packet for node (ADVERT only), got %d", result.Total)
+	}
+	for _, pkt := range result.Packets {
+		if pkt["hash"] == "chat_hash_673" {
+			t.Errorf("GRP_TXT with pubkey in message text was incorrectly returned for node query")
+		}
+	}
+}

cmd/server/issue810_repro_test.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/gorilla/mux"
+)
+
+// TestRepro810 reproduces #810: when the longest-path observation has NULL
+// resolved_path but a shorter-path observation has one, fetchResolvedPathForTxBest
+// returns nil → /api/nodes/{pk}/health.recentPackets[].resolved_path is missing
+// while /api/packets shows it.
+func TestRepro810(t *testing.T) {
+	db := setupTestDB(t)
+	now := time.Now().UTC()
+	recent := now.Add(-1 * time.Hour).Format(time.RFC3339)
+	recentEpoch := now.Add(-1 * time.Hour).Unix()
+	db.conn.Exec(`INSERT INTO observers (id, name, last_seen, first_seen, packet_count) VALUES ('obs1','O1',?, '2026-01-01T00:00:00Z', 100)`, recent)
+	db.conn.Exec(`INSERT INTO observers (id, name, last_seen, first_seen, packet_count) VALUES ('obs2','O2',?, '2026-01-01T00:00:00Z', 100)`, recent)
+	db.conn.Exec(`INSERT INTO nodes (public_key, name, role, last_seen, first_seen, advert_count) VALUES ('aabbccdd11223344','R','repeater',?, '2026-01-01T00:00:00Z', 1)`, recent)
+	db.conn.Exec(`INSERT INTO transmissions (raw_hex, hash, first_seen, route_type, payload_type, decoded_json) VALUES ('AABB','testhash00000001',?,1,4,'{"pubKey":"aabbccdd11223344","type":"ADVERT"}')`, recent)
+	// Longest-path obs WITHOUT resolved_path
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp) VALUES (1,1,12.5,-90,'["aa","bb","cc"]',?)`, recentEpoch)
+	// Shorter-path obs WITH resolved_path
+	db.conn.Exec(`INSERT INTO observations (transmission_id, observer_idx, snr, rssi, path_json, timestamp, resolved_path) VALUES (1,2,8.0,-95,'["aa","bb"]',?,'["aabbccdd11223344","eeff00112233aabb"]')`, recentEpoch-100)
+
+	cfg := &Config{Port: 3000}
+	hub := NewHub()
+	srv := NewServer(db, cfg, hub)
+	store := NewPacketStore(db, nil)
+	if err := store.Load(); err != nil {
+		t.Fatal(err)
+	}
+	srv.store = store
+	router := mux.NewRouter()
+	srv.RegisterRoutes(router)
+
+	// Sanity: /api/packets should show resolved_path for this tx.
+	reqP := httptest.NewRequest("GET", "/api/packets?limit=10", nil)
+	wP := httptest.NewRecorder()
+	router.ServeHTTP(wP, reqP)
+	var pktsBody map[string]interface{}
+	json.Unmarshal(wP.Body.Bytes(), &pktsBody)
+	pkts, _ := pktsBody["packets"].([]interface{})
+	hasOnPackets := false
+	for _, p := range pkts {
+		pm := p.(map[string]interface{})
+		if pm["hash"] == "testhash00000001" && pm["resolved_path"] != nil {
+			hasOnPackets = true
+		}
+	}
+	if !hasOnPackets {
+		t.Fatal("precondition: /api/packets must report resolved_path for tx")
+	}
+
+	req := httptest.NewRequest("GET", "/api/nodes/aabbccdd11223344/health", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+	var body map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &body)
+	rp, _ := body["recentPackets"].([]interface{})
+	if len(rp) == 0 {
+		t.Fatal("no recentPackets")
+	}
+	for _, p := range rp {
+		pm := p.(map[string]interface{})
+		if pm["hash"] == "testhash00000001" {
+			if pm["resolved_path"] == nil {
+				t.Fatal("BUG #810: /health.recentPackets resolved_path is nil despite /api/packets reporting it")
+			}
+			return
+		}
+	}
+	t.Fatal("tx not found in recentPackets")
+}

cmd/server/issue871_test.go

@@ -0,0 +1,194 @@
+package main
+
+import (
+	"database/sql"
+	"testing"
+	"time"
+	"path/filepath"
+
+	_ "modernc.org/sqlite"
+)
+
+// setupTestDB871 creates a test DB with schema and returns a read-only *DB handle.
+func setupTestDB871(t *testing.T) (*DB, *sql.DB) {
+	t.Helper()
+	dbPath := filepath.Join(t.TempDir(), "test871.db")
+
+	// Open writable connection for setup
+	rw, err := sql.Open("sqlite", "file:"+dbPath+"?_journal_mode=WAL")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, err = rw.Exec(`
+		CREATE TABLE IF NOT EXISTS nodes (
+			public_key TEXT PRIMARY KEY,
+			name TEXT, role TEXT,
+			lat REAL, lon REAL,
+			last_seen TEXT, first_seen TEXT,
+			advert_count INTEGER DEFAULT 0,
+			battery_mv INTEGER, temperature_c REAL
+		);
+		CREATE TABLE IF NOT EXISTS transmissions (
+			id INTEGER PRIMARY KEY AUTOINCREMENT,
+			raw_hex TEXT NOT NULL,
+			hash TEXT NOT NULL UNIQUE,
+			first_seen TEXT NOT NULL,
+			route_type INTEGER,
+			payload_type INTEGER,
+			payload_version INTEGER,
+			decoded_json TEXT,
+			created_at TEXT DEFAULT (datetime('now'))
+		);
+		CREATE TABLE IF NOT EXISTS observers (
+			rowid INTEGER PRIMARY KEY AUTOINCREMENT,
+			id TEXT NOT NULL UNIQUE,
+			name TEXT
+		);
+		CREATE TABLE IF NOT EXISTS observations (
+			id INTEGER PRIMARY KEY AUTOINCREMENT,
+			transmission_id INTEGER NOT NULL,
+			observer_id TEXT,
+			observer_name TEXT,
+			direction TEXT,
+			snr REAL, rssi REAL, score INTEGER,
+			path_json TEXT, timestamp TEXT
+		);
+	`)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Open read-only handle for the store
+	db, err := OpenDB(dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	t.Cleanup(func() {
+		db.Close()
+		rw.Close()
+	})
+
+	return db, rw
+}
+
+// TestEnrichObsFallbackToDB verifies that enrichObs falls back to the DB when
+// the parent transmission has been evicted from memory (#871 root cause).
+func TestEnrichObsFallbackToDB(t *testing.T) {
+	db, rw := setupTestDB871(t)
+
+	now := time.Now().UTC().Format(time.RFC3339)
+	_, err := rw.Exec(
+		`INSERT INTO transmissions (raw_hex, hash, first_seen, payload_type, decoded_json) VALUES (?, ?, ?, ?, ?)`,
+		"aabbcc", "abc123", now, 4, `{"pubKey":"pk1"}`,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	store := NewPacketStore(db, &PacketStoreConfig{})
+
+	// Observation references tx_id=1, but tx is NOT in byTxID (simulates eviction)
+	obs := &StoreObs{
+		ID:             1,
+		TransmissionID: 1,
+		ObserverID:     "obs1",
+		ObserverName:   "Observer1",
+		Timestamp:      now,
+	}
+
+	result := store.enrichObs(obs)
+
+	// hash must be present from DB fallback
+	if result["hash"] == nil {
+		t.Errorf("enrichObs: hash is nil — DB fallback failed")
+	}
+	if h, ok := result["hash"].(string); !ok || h != "abc123" {
+		t.Errorf("enrichObs: expected hash 'abc123', got %v", result["hash"])
+	}
+	if result["payload_type"] == nil {
+		t.Errorf("enrichObs: payload_type is nil — DB fallback failed")
+	}
+
+	// When tx IS in memory, it should use the in-memory path
+	pt := 4
+	store.byTxID[1] = &StoreTx{
+		ID: 1, Hash: "abc123", FirstSeen: now,
+		PayloadType: &pt, RawHex: "aabbcc",
+	}
+
+	result2 := store.enrichObs(obs)
+	if result2["hash"] == nil {
+		t.Errorf("enrichObs with in-memory tx: hash is nil")
+	}
+}
+
+// TestGetNodeHealthRecentPacketsNoNilFields verifies that GetNodeHealth's
+// recentPackets never contains entries with nil hash or timestamp.
+func TestGetNodeHealthRecentPacketsNoNilFields(t *testing.T) {
+	db, rw := setupTestDB871(t)
+
+	now := time.Now().UTC().Format(time.RFC3339)
+	_, err := rw.Exec(
+		`INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)`,
+		"pk1", "TestNode", "repeater", now,
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	store := NewPacketStore(db, &PacketStoreConfig{})
+
+	pt := 4
+	tx := &StoreTx{
+		ID: 1, Hash: "hash1", FirstSeen: now,
+		PayloadType: &pt, DecodedJSON: `{"pubKey":"pk1"}`,
+		obsKeys: make(map[string]bool), observerSet: make(map[string]bool),
+	}
+	store.byTxID[1] = tx
+	store.byHash["hash1"] = tx
+	store.byNode["pk1"] = []*StoreTx{tx}
+	store.nodeHashes["pk1"] = map[string]bool{"hash1": true}
+
+	result, err := store.GetNodeHealth("pk1")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if result == nil {
+		t.Fatal("GetNodeHealth returned nil")
+	}
+
+	packets, ok := result["recentPackets"].([]map[string]interface{})
+	if !ok {
+		t.Fatal("recentPackets is not []map[string]interface{}")
+	}
+
+	for i, p := range packets {
+		if p["hash"] == nil {
+			t.Errorf("recentPackets[%d] has nil hash", i)
+		}
+		if p["timestamp"] == nil {
+			t.Errorf("recentPackets[%d] has nil timestamp", i)
+		}
+	}
+}
+
+// TestEnrichObsNilDB verifies enrichObs doesn't panic when db is nil.
+func TestEnrichObsNilDB(t *testing.T) {
+	store := &PacketStore{
+		byTxID:  make(map[int]*StoreTx),
+		byObsID: make(map[int]*StoreObs),
+	}
+
+	obs := &StoreObs{
+		ID: 1, TransmissionID: 999,
+		Timestamp: "2026-01-01T00:00:00Z",
+	}
+
+	// Should not panic
+	result := store.enrichObs(obs)
+	if result["hash"] != nil {
+		t.Errorf("expected nil hash when no DB and no in-memory tx, got %v", result["hash"])
+	}
+}

cmd/server/main.go

@@ -111,6 +111,14 @@ func main() {
 	// Resolve DB path
 	resolvedDB := cfg.ResolveDBPath(configDir)
 	log.Printf("[config] port=%d db=%s public=%s", cfg.Port, resolvedDB, publicDir)
+	if len(cfg.NodeBlacklist) > 0 {
+		log.Printf("[config] nodeBlacklist: %d node(s) will be hidden from API", len(cfg.NodeBlacklist))
+		for _, pk := range cfg.NodeBlacklist {
+			if trimmed := strings.ToLower(strings.TrimSpace(pk)); trimmed != "" {
+				log.Printf("[config]   blacklisted: %s", trimmed)
+			}
+		}
+	}
 
 	// Open database
 	database, err := OpenDB(resolvedDB)
@@ -325,6 +333,40 @@ func main() {
 		log.Printf("[metrics-prune] auto-prune enabled: metrics older than %d days", metricsDays)
 	}
 
+	// Auto-prune stale observers
+	var stopObserverPrune func()
+	{
+		observerDays := cfg.ObserverDaysOrDefault()
+		if observerDays <= -1 {
+			// -1 means keep forever, skip
+		} else {
+			observerPruneTicker := time.NewTicker(24 * time.Hour)
+			observerPruneDone := make(chan struct{})
+			stopObserverPrune = func() {
+				observerPruneTicker.Stop()
+				close(observerPruneDone)
+			}
+			go func() {
+				defer func() {
+					if r := recover(); r != nil {
+						log.Printf("[observer-prune] panic recovered: %v", r)
+					}
+				}()
+				time.Sleep(3 * time.Minute) // stagger after metrics prune
+				database.RemoveStaleObservers(observerDays)
+				for {
+					select {
+					case <-observerPruneTicker.C:
+						database.RemoveStaleObservers(observerDays)
+					case <-observerPruneDone:
+						return
+					}
+				}
+			}()
+			log.Printf("[observer-prune] auto-prune enabled: observers not seen in %d days will be removed", observerDays)
+		}
+	}
+
 	// Auto-prune old neighbor edges
 	var stopEdgePrune func()
 	{
@@ -386,6 +428,9 @@ func main() {
 		if stopMetricsPrune != nil {
 			stopMetricsPrune()
 		}
+		if stopObserverPrune != nil {
+			stopObserverPrune()
+		}
 		if stopEdgePrune != nil {
 			stopEdgePrune()
 		}
@@ -412,6 +457,9 @@ func main() {
 	// Start async backfill in background — HTTP is now available.
 	go backfillResolvedPathsAsync(store, dbPath, 5000, 100*time.Millisecond, cfg.BackfillHours())
 
+	// Migrate old content hashes in background (one-time, idempotent).
+	go migrateContentHashesAsync(store, 5000, 100*time.Millisecond)
+
 	if err := httpServer.ListenAndServe(); err != http.ErrServerClosed {
 		log.Fatalf("[server] %v", err)
 	}

cmd/server/memory.go

@@ -0,0 +1,132 @@
+package main
+
+import (
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// MemorySnapshot is a point-in-time view of process memory across several
+// vantage points. Values are in MB (1024*1024 bytes), rounded to one decimal.
+//
+// Field invariants (typical, not guaranteed under exotic conditions):
+//
+//	processRSSMB  >=  goSysMB  >=  goHeapInuseMB  >=  storeDataMB
+//
+//   - processRSSMB is what the kernel charges the process (resident set).
+//     Read from /proc/self/status `VmRSS:` on Linux; falls back to goSysMB
+//     on other platforms or when /proc is unavailable.
+//   - goSysMB is the total memory obtained from the OS by the Go runtime
+//     (heap, stacks, GC metadata, mspans, mcache, etc.). Includes
+//     fragmentation and unused-but-mapped span overhead.
+//   - goHeapInuseMB is the live, in-use Go heap (HeapInuse). Excludes
+//     idle spans and runtime overhead.
+//   - storeDataMB is the in-store packet byte estimate (transmissions +
+//     observations). Subset of HeapInuse. Does not include index maps,
+//     analytics caches, broadcast queues, or runtime overhead. Used as
+//     the input to the eviction watermark.
+//
+// processRSSMB and storeDataMB are monotonic only relative to ingest +
+// eviction; both can shrink when packets age out. goHeapInuseMB and goSysMB
+// fluctuate with GC.
+//
+// cgoBytesMB intentionally absent: this build uses the pure-Go
+// modernc.org/sqlite driver, so there is no cgo allocator to measure.
+// Reintroduce only if we ever switch back to mattn/go-sqlite3.
+type MemorySnapshot struct {
+	ProcessRSSMB  float64 `json:"processRSSMB"`
+	GoHeapInuseMB float64 `json:"goHeapInuseMB"`
+	GoSysMB       float64 `json:"goSysMB"`
+	StoreDataMB   float64 `json:"storeDataMB"`
+}
+
+// rssCache rate-limits the /proc/self/status read. Go memory stats are
+// already cached by Server.getMemStats (5s TTL). We use a tighter 1s TTL
+// here so processRSSMB stays reasonably fresh during ops debugging
+// without paying the syscall cost on every /api/stats hit.
+var (
+	rssCacheMu       sync.Mutex
+	rssCacheValueMB  float64
+	rssCacheCachedAt time.Time
+)
+
+const rssCacheTTL = 1 * time.Second
+
+// getMemorySnapshot composes a MemorySnapshot using the Server's existing
+// runtime.MemStats cache (5s TTL, used by /api/health and /api/perf too)
+// plus a rate-limited /proc RSS read. storeDataMB is supplied by the
+// caller because the packet store is the source of truth.
+func (s *Server) getMemorySnapshot(storeDataMB float64) MemorySnapshot {
+	ms := s.getMemStats()
+
+	rssCacheMu.Lock()
+	if time.Since(rssCacheCachedAt) > rssCacheTTL {
+		rssCacheValueMB = readProcRSSMB()
+		rssCacheCachedAt = time.Now()
+	}
+	rssMB := rssCacheValueMB
+	rssCacheMu.Unlock()
+
+	if rssMB <= 0 {
+		// Fallback when /proc is unavailable (non-Linux, sandboxes, etc.).
+		// runtime.Sys is an upper bound on Go-attributable memory and a
+		// reasonable proxy for pure-Go builds.
+		rssMB = float64(ms.Sys) / 1048576.0
+	}
+
+	return MemorySnapshot{
+		ProcessRSSMB:  roundMB(rssMB),
+		GoHeapInuseMB: roundMB(float64(ms.HeapInuse) / 1048576.0),
+		GoSysMB:       roundMB(float64(ms.Sys) / 1048576.0),
+		StoreDataMB:   roundMB(storeDataMB),
+	}
+}
+
+// readProcRSSMB parses /proc/self/status for the VmRSS line. Returns 0 on
+// any failure (file missing, malformed line, parse error) — the caller
+// then uses a runtime fallback. Linux only; macOS/Windows return 0.
+//
+// Safety notes (djb): the file path is hard-coded, no untrusted input is
+// concatenated. We bound the read at 8 KiB (the whole status file is
+// well under 4 KiB on modern kernels) so a corrupt /proc can't OOM us.
+// We only parse digits with strconv; no shell, no exec, no format strings.
+func readProcRSSMB() float64 {
+	const maxStatusBytes = 8 * 1024
+	f, err := os.Open("/proc/self/status")
+	if err != nil {
+		return 0
+	}
+	defer f.Close()
+
+	buf := make([]byte, maxStatusBytes)
+	n, err := f.Read(buf)
+	if err != nil && n == 0 {
+		return 0
+	}
+	for _, line := range strings.Split(string(buf[:n]), "\n") {
+		if !strings.HasPrefix(line, "VmRSS:") {
+			continue
+		}
+		// Format: "VmRSS:\t   123456 kB"
+		fields := strings.Fields(line[len("VmRSS:"):])
+		if len(fields) < 2 {
+			return 0
+		}
+		kb, err := strconv.ParseFloat(fields[0], 64)
+		if err != nil || kb < 0 {
+			return 0
+		}
+		// Unit is kB per kernel convention; convert to MB.
+		return kb / 1024.0
+	}
+	return 0
+}
+
+func roundMB(v float64) float64 {
+	if v < 0 {
+		return 0
+	}
+	return float64(int64(v*10+0.5)) / 10.0
+}

cmd/server/multibyte_capability_test.go

@@ -6,10 +6,17 @@ import (
 	"fmt"
 	"strings"
 	"testing"
+	"time"
 
 	_ "modernc.org/sqlite"
 )
 
+// recentTS returns a timestamp string N hours ago, ensuring test data
+// stays within the 7-day advert window used by computeNodeHashSizeInfo.
+func recentTS(hoursAgo int) string {
+	return time.Now().UTC().Add(-time.Duration(hoursAgo) * time.Hour).Format("2006-01-02T15:04:05.000Z")
+}
+
 // setupCapabilityTestDB creates a minimal in-memory DB with nodes table.
 func setupCapabilityTestDB(t *testing.T) *DB {
 	t.Helper()
@@ -69,7 +76,7 @@ func makeTestAdvert(pubkey string, hashSize int) *StoreTx {
 		PayloadType: &pt,
 		DecodedJSON: string(decoded),
 		PathJSON:    `["` + prefix + `"]`,
-		FirstSeen:   "2026-04-11T00:00:00.000Z",
+		FirstSeen:   recentTS(24),
 	}
 }
 
@@ -80,12 +87,12 @@ func TestMultiByteCapability_Confirmed(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepA", "repeater", "2026-04-11T00:00:00Z")
+		"aabbccdd11223344", "RepA", "repeater", recentTS(24))
 
 	store := NewPacketStore(db, nil)
 	addTestPacket(store, makeTestAdvert("aabbccdd11223344", 2))
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -107,7 +114,7 @@ func TestMultiByteCapability_Suspected(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepB", "repeater", "2026-04-10T00:00:00Z")
+		"aabbccdd11223344", "RepB", "repeater", recentTS(48))
 
 	store := NewPacketStore(db, nil)
 
@@ -119,11 +126,11 @@ func TestMultiByteCapability_Suspected(t *testing.T) {
 		RawHex:      rawHex,
 		PayloadType: &pt,
 		PathJSON:    `["aabb"]`,
-		FirstSeen:   "2026-04-10T00:00:00.000Z",
+		FirstSeen:   recentTS(48),
 	}
 	addTestPacket(store, pkt)
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -145,14 +152,14 @@ func TestMultiByteCapability_Unknown(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepC", "repeater", "2026-04-08T00:00:00Z")
+		"aabbccdd11223344", "RepC", "repeater", recentTS(72))
 
 	store := NewPacketStore(db, nil)
 
 	// Advert with 1-byte hash only
 	addTestPacket(store, makeTestAdvert("aabbccdd11223344", 1))
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -173,9 +180,9 @@ func TestMultiByteCapability_PrefixCollision(t *testing.T) {
 
 	// Two repeaters sharing 1-byte prefix "aa"
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabb000000000001", "RepConfirmed", "repeater", "2026-04-11T00:00:00Z")
+		"aabb000000000001", "RepConfirmed", "repeater", recentTS(24))
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aacc000000000002", "RepOther", "repeater", "2026-04-11T00:00:00Z")
+		"aacc000000000002", "RepOther", "repeater", recentTS(24))
 
 	store := NewPacketStore(db, nil)
 
@@ -190,11 +197,11 @@ func TestMultiByteCapability_PrefixCollision(t *testing.T) {
 		RawHex:      rawHex,
 		PayloadType: &pt,
 		PathJSON:    `["aa"]`,
-		FirstSeen:   "2026-04-10T00:00:00.000Z",
+		FirstSeen:   recentTS(48),
 	}
 	addTestPacket(store, pkt)
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 2 {
 		t.Fatalf("expected 2 entries, got %d", len(caps))
 	}
@@ -221,7 +228,7 @@ func TestMultiByteCapability_TraceExcluded(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepTrace", "repeater", "2026-04-10T00:00:00Z")
+		"aabbccdd11223344", "RepTrace", "repeater", recentTS(48))
 
 	store := NewPacketStore(db, nil)
 
@@ -233,11 +240,11 @@ func TestMultiByteCapability_TraceExcluded(t *testing.T) {
 		RawHex:      rawHex,
 		PayloadType: &pt,
 		PathJSON:    `["aabb"]`,
-		FirstSeen:   "2026-04-10T00:00:00.000Z",
+		FirstSeen:   recentTS(48),
 	}
 	addTestPacket(store, pkt)
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -253,7 +260,7 @@ func TestMultiByteCapability_NonTraceStillSuspected(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepNonTrace", "repeater", "2026-04-10T00:00:00Z")
+		"aabbccdd11223344", "RepNonTrace", "repeater", recentTS(48))
 
 	store := NewPacketStore(db, nil)
 
@@ -265,11 +272,11 @@ func TestMultiByteCapability_NonTraceStillSuspected(t *testing.T) {
 		RawHex:      rawHex,
 		PayloadType: &pt,
 		PathJSON:    `["aabb"]`,
-		FirstSeen:   "2026-04-10T00:00:00.000Z",
+		FirstSeen:   recentTS(48),
 	}
 	addTestPacket(store, pkt)
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -285,7 +292,7 @@ func TestMultiByteCapability_ConfirmedUnaffectedByTraceExclusion(t *testing.T) {
 	defer db.conn.Close()
 
 	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
-		"aabbccdd11223344", "RepConfirmedTrace", "repeater", "2026-04-11T00:00:00Z")
+		"aabbccdd11223344", "RepConfirmedTrace", "repeater", recentTS(24))
 
 	store := NewPacketStore(db, nil)
 
@@ -300,11 +307,11 @@ func TestMultiByteCapability_ConfirmedUnaffectedByTraceExclusion(t *testing.T) {
 		RawHex:      rawHex,
 		PayloadType: &pt,
 		PathJSON:    `["aabb"]`,
-		FirstSeen:   "2026-04-10T00:00:00.000Z",
+		FirstSeen:   recentTS(48),
 	}
 	addTestPacket(store, pkt)
 
-	caps := store.computeMultiByteCapability()
+	caps := store.computeMultiByteCapability(nil)
 	if len(caps) != 1 {
 		t.Fatalf("expected 1 entry, got %d", len(caps))
 	}
@@ -312,3 +319,117 @@ func TestMultiByteCapability_ConfirmedUnaffectedByTraceExclusion(t *testing.T) {
 		t.Errorf("expected confirmed (unaffected by TRACE), got %s", caps[0].Status)
 	}
 }
+
+// TestMultiByteCapability_CompanionConfirmed tests that a companion with
+// multi-byte advert is classified as "confirmed", not "unknown" (Bug 1, #754).
+func TestMultiByteCapability_CompanionConfirmed(t *testing.T) {
+	db := setupCapabilityTestDB(t)
+	defer db.conn.Close()
+
+	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
+		"aabbccdd11223344", "CompA", "companion", recentTS(24))
+
+	store := NewPacketStore(db, nil)
+	addTestPacket(store, makeTestAdvert("aabbccdd11223344", 2))
+
+	caps := store.computeMultiByteCapability(nil)
+	if len(caps) != 1 {
+		t.Fatalf("expected 1 entry, got %d", len(caps))
+	}
+	if caps[0].Status != "confirmed" {
+		t.Errorf("expected confirmed for companion, got %s", caps[0].Status)
+	}
+	if caps[0].Role != "companion" {
+		t.Errorf("expected role companion, got %s", caps[0].Role)
+	}
+	if caps[0].Evidence != "advert" {
+		t.Errorf("expected advert evidence, got %s", caps[0].Evidence)
+	}
+}
+
+// TestMultiByteCapability_RoleColumnPopulated tests that the Role field is
+// populated for all node types (Bug 2, #754).
+func TestMultiByteCapability_RoleColumnPopulated(t *testing.T) {
+	db := setupCapabilityTestDB(t)
+	defer db.conn.Close()
+
+	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
+		"aabb000000000001", "Rep1", "repeater", recentTS(24))
+	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
+		"ccdd000000000002", "Comp1", "companion", recentTS(24))
+	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
+		"eeff000000000003", "Room1", "room_server", recentTS(24))
+
+	store := NewPacketStore(db, nil)
+	addTestPacket(store, makeTestAdvert("aabb000000000001", 2))
+	addTestPacket(store, makeTestAdvert("ccdd000000000002", 2))
+	addTestPacket(store, makeTestAdvert("eeff000000000003", 1))
+
+	caps := store.computeMultiByteCapability(nil)
+	if len(caps) != 3 {
+		t.Fatalf("expected 3 entries, got %d", len(caps))
+	}
+
+	roleByName := map[string]string{}
+	for _, c := range caps {
+		roleByName[c.Name] = c.Role
+	}
+	if roleByName["Rep1"] != "repeater" {
+		t.Errorf("Rep1 role: expected repeater, got %s", roleByName["Rep1"])
+	}
+	if roleByName["Comp1"] != "companion" {
+		t.Errorf("Comp1 role: expected companion, got %s", roleByName["Comp1"])
+	}
+	if roleByName["Room1"] != "room_server" {
+		t.Errorf("Room1 role: expected room_server, got %s", roleByName["Room1"])
+	}
+}
+
+// TestMultiByteCapability_AdopterEvidenceTakesPrecedence tests that when
+// adopter data shows hashSize >= 2 but path evidence says "suspected",
+// the node is upgraded to "confirmed" (Bug 3, #754).
+func TestMultiByteCapability_AdopterEvidenceTakesPrecedence(t *testing.T) {
+	db := setupCapabilityTestDB(t)
+	defer db.conn.Close()
+
+	db.conn.Exec("INSERT INTO nodes (public_key, name, role, last_seen) VALUES (?, ?, ?, ?)",
+		"aabbccdd11223344", "RepAdopter", "repeater", recentTS(24))
+
+	store := NewPacketStore(db, nil)
+
+	// Only a path-based packet (no advert) — would normally be "suspected"
+	pathByte := buildPathByte(2, 1)
+	rawHex := "01" + pathByte + "aabb"
+	pt := 1
+	pkt := &StoreTx{
+		RawHex:      rawHex,
+		PayloadType: &pt,
+		PathJSON:    `["aabb"]`,
+		FirstSeen:   recentTS(48),
+	}
+	addTestPacket(store, pkt)
+
+	// Without adopter data: should be suspected
+	caps := store.computeMultiByteCapability(nil)
+	capByName := map[string]MultiByteCapEntry{}
+	for _, c := range caps {
+		capByName[c.Name] = c
+	}
+	if capByName["RepAdopter"].Status != "suspected" {
+		t.Errorf("without adopter data: expected suspected, got %s", capByName["RepAdopter"].Status)
+	}
+
+	// With adopter data showing hashSize 2: should be confirmed
+	adopterHS := map[string]int{"aabbccdd11223344": 2}
+	caps = store.computeMultiByteCapability(adopterHS)
+	capByName = map[string]MultiByteCapEntry{}
+	for _, c := range caps {
+		capByName[c.Name] = c
+	}
+	if capByName["RepAdopter"].Status != "confirmed" {
+		t.Errorf("with adopter data: expected confirmed, got %s", capByName["RepAdopter"].Status)
+	}
+	if capByName["RepAdopter"].Evidence != "advert" {
+		t.Errorf("with adopter data: expected advert evidence, got %s", capByName["RepAdopter"].Evidence)
+	}
+}

cmd/server/neighbor_api.go

@@ -94,6 +94,10 @@ func (s *Server) getNeighborGraph() *NeighborGraph {
 
 func (s *Server) handleNodeNeighbors(w http.ResponseWriter, r *http.Request) {
 	pubkey := strings.ToLower(mux.Vars(r)["pubkey"])
+	if s.cfg.IsBlacklisted(pubkey) {
+		writeError(w, 404, "Not found")
+		return
+	}
 
 	minCount := 1
 	if v := r.URL.Query().Get("min_count"); v != "" {
@@ -272,6 +276,11 @@ func (s *Server) handleNeighborGraph(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 
+		// Filter blacklisted nodes from graph.
+		if s.cfg != nil && (s.cfg.IsBlacklisted(e.NodeA) || s.cfg.IsBlacklisted(e.NodeB)) {
+			continue
+		}
+
 		ge := GraphEdge{
 			Source:        e.NodeA,
 			Target:        e.NodeB,
@@ -373,6 +382,26 @@ func (s *Server) buildNodeInfoMap() map[string]nodeInfo {
 	for _, n := range nodes {
 		m[strings.ToLower(n.PublicKey)] = n
 	}
+
+	// Enrich observer-only nodes: if an observer pubkey isn't already in the
+	// map (i.e. it's not also a repeater/companion), add it with role "observer".
+	if s.db != nil {
+		rows, err := s.db.conn.Query("SELECT id, name FROM observers")
+		if err == nil {
+			defer rows.Close()
+			for rows.Next() {
+				var id, name string
+				if rows.Scan(&id, &name) != nil {
+					continue
+				}
+				key := strings.ToLower(id)
+				if _, exists := m[key]; !exists {
+					m[key] = nodeInfo{PublicKey: id, Name: name, Role: "observer"}
+				}
+			}
+		}
+	}
+
 	return m
 }
 

cmd/server/neighbor_api_test.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"database/sql"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
@@ -8,6 +9,7 @@ import (
 	"time"
 
 	"github.com/gorilla/mux"
+	_ "modernc.org/sqlite"
 )
 
 // ─── Helpers ───────────────────────────────────────────────────────────────────
@@ -457,3 +459,69 @@ func TestNeighborGraphAPI_ResponseShape(t *testing.T) {
 		}
 	}
 }
+
+// ─── Tests: buildNodeInfoMap observer enrichment (#753) ────────────────────────
+
+func TestBuildNodeInfoMap_ObserverEnrichment(t *testing.T) {
+	// Create a temp SQLite DB with nodes and observers tables.
+	tmpDir := t.TempDir()
+	dbPath := tmpDir + "/test.db"
+
+	conn, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer conn.Close()
+
+	// Create tables
+	for _, stmt := range []string{
+		"CREATE TABLE nodes (public_key TEXT, name TEXT, role TEXT, lat REAL, lon REAL)",
+		"CREATE TABLE observers (id TEXT, name TEXT)",
+		"INSERT INTO nodes VALUES ('AAAA1111', 'Repeater-1', 'repeater', 0, 0)",
+		"INSERT INTO observers VALUES ('BBBB2222', 'Observer-Alpha')",
+		"INSERT INTO observers VALUES ('AAAA1111', 'Obs-also-repeater')",
+	} {
+		if _, err := conn.Exec(stmt); err != nil {
+			t.Fatalf("exec %q: %v", stmt, err)
+		}
+	}
+	conn.Close()
+
+	// Open via our DB wrapper
+	db, err := OpenDB(dbPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.conn.Close()
+
+	// Build a PacketStore with this DB (minimal — just need getCachedNodesAndPM)
+	store := NewPacketStore(db, nil)
+	store.Load()
+
+	srv := &Server{
+		db:        db,
+		store:     store,
+		perfStats: NewPerfStats(),
+	}
+
+	m := srv.buildNodeInfoMap()
+
+	// AAAA1111 should be from nodes table (repeater), NOT overwritten by observer
+	if info, ok := m["aaaa1111"]; !ok {
+		t.Error("expected aaaa1111 in map")
+	} else if info.Role != "repeater" {
+		t.Errorf("expected role=repeater for aaaa1111, got %q", info.Role)
+	}
+
+	// BBBB2222 should be enriched from observers table
+	if info, ok := m["bbbb2222"]; !ok {
+		t.Error("expected bbbb2222 in map (observer-only node)")
+	} else {
+		if info.Role != "observer" {
+			t.Errorf("expected role=observer for bbbb2222, got %q", info.Role)
+		}
+		if info.Name != "Observer-Alpha" {
+			t.Errorf("expected name=Observer-Alpha for bbbb2222, got %q", info.Name)
+		}
+	}
+}

cmd/server/neighbor_graph.go

@@ -166,7 +166,7 @@ func BuildFromStoreWithLog(store *PacketStore, enableLog bool) *NeighborGraph {
 
 	// Phase 1: Extract edges from every transmission + observation.
 	for _, tx := range packets {
-		isAdvert := tx.PayloadType != nil && *tx.PayloadType == 4
+		isAdvert := tx.PayloadType != nil && *tx.PayloadType == PayloadADVERT
 		fromNode := extractFromNode(tx)
 		// Pre-compute lowered originator once per tx (not per observation).
 		fromLower := ""

cmd/server/neighbor_persist.go

@@ -381,7 +381,13 @@ func backfillResolvedPathsAsync(store *PacketStore, dbPath string, chunkSize int
 			}
 		}
 		for _, obs := range tx.Observations {
-			if obs.ResolvedPath == nil && obs.PathJSON != "" && obs.PathJSON != "[]" {
+			// Check if this observation has been resolved: look up in the index.
+			// If the tx has no reverse-map entries AND path is non-empty, it needs backfill.
+			hasRP := false
+			if _, ok := store.resolvedPubkeyReverse[tx.ID]; ok {
+				hasRP = true
+			}
+			if !hasRP && obs.PathJSON != "" && obs.PathJSON != "[]" {
 				allPending = append(allPending, obsRef{
 					obsID:       obs.ID,
 					pathJSON:    obs.PathJSON,
@@ -482,24 +488,61 @@ func backfillResolvedPathsAsync(store *PacketStore, dbPath string, chunkSize int
 				}
 			}
 
-			// Update in-memory state and re-pick best observation under a single
-			// write lock. The per-tx pickBestObservation is O(observations) which is
-			// typically <10 per tx — negligible cost vs. the race risk of splitting
-			// the lock (pollAndMerge can append to tx.Observations concurrently).
+			// Update in-memory state: update resolved pubkey index, re-pick best observation,
+			// and invalidate LRU cache entries for backfilled observations (#800).
+			//
+			// Lock ordering: always take s.mu BEFORE lruMu. The read path
+			// (fetchResolvedPathForObs) takes lruMu independently of s.mu,
+			// so we must NOT hold s.mu while taking lruMu. Instead, collect
+			// obsIDs to invalidate under s.mu, release it, then take lruMu.
 			store.mu.Lock()
 			affectedSet := make(map[string]bool)
+			lruInvalidate := make([]int, 0, len(results))
 			for _, r := range results {
-				if obs, ok := store.byObsID[r.obsID]; ok {
-					obs.ResolvedPath = r.rp
-				}
+				// Remove old index entries for this tx, then re-add with new pubkeys
 				if !affectedSet[r.txHash] {
 					affectedSet[r.txHash] = true
 					if tx, ok := store.byHash[r.txHash]; ok {
-						pickBestObservation(tx)
+						store.removeFromResolvedPubkeyIndex(tx.ID)
 					}
 				}
+				// Add new resolved pubkeys to index
+				if tx, ok := store.byHash[r.txHash]; ok {
+					pks := extractResolvedPubkeys(r.rp)
+					store.addToResolvedPubkeyIndex(tx.ID, pks)
+					// Update byNode for relay nodes
+					for _, pk := range pks {
+						store.addToByNode(tx, pk)
+					}
+					// Update byPathHop resolved-key entries
+					hopsSeen := make(map[string]bool)
+					for _, hop := range txGetParsedPath(tx) {
+						hopsSeen[strings.ToLower(hop)] = true
+					}
+					for _, pk := range pks {
+						if !hopsSeen[pk] {
+							hopsSeen[pk] = true
+							store.byPathHop[pk] = append(store.byPathHop[pk], tx)
+						}
+					}
+				}
+				lruInvalidate = append(lruInvalidate, r.obsID)
+			}
+			// Re-pick best observation for affected transmissions
+			for txHash := range affectedSet {
+				if tx, ok := store.byHash[txHash]; ok {
+					pickBestObservation(tx)
+				}
 			}
 			store.mu.Unlock()
+
+			// Invalidate LRU entries AFTER releasing s.mu to maintain lock
+			// ordering (lruMu must never be taken while s.mu is held).
+			store.lruMu.Lock()
+			for _, obsID := range lruInvalidate {
+				store.lruDelete(obsID)
+			}
+			store.lruMu.Unlock()
 		}
 
 		totalProcessed += len(chunk)
@@ -525,7 +568,7 @@ type edgeCandidate struct {
 // For ADVERTs: originator↔path[0] (if unambiguous). For ALL types: observer↔path[last] (if unambiguous).
 // Also handles zero-hop ADVERTs (originator↔observer direct link).
 func extractEdgesFromObs(obs *StoreObs, tx *StoreTx, pm *prefixMap) []edgeCandidate {
-	isAdvert := tx.PayloadType != nil && *tx.PayloadType == 4
+	isAdvert := tx.PayloadType != nil && *tx.PayloadType == PayloadADVERT
 	fromNode := extractFromNode(tx)
 	path := parsePathJSON(obs.PathJSON)
 	observerPK := strings.ToLower(obs.ObserverID)

cmd/server/neighbor_persist_test.go

@@ -27,7 +27,7 @@ func createTestDBWithSchema(t *testing.T) (*DB, string) {
 		id INTEGER PRIMARY KEY AUTOINCREMENT,
 		raw_hex TEXT, hash TEXT UNIQUE, first_seen TEXT,
 		route_type INTEGER, payload_type INTEGER, payload_version INTEGER,
-		decoded_json TEXT
+		decoded_json TEXT, channel_hash TEXT DEFAULT NULL
 	)`)
 	conn.Exec(`CREATE TABLE observers (
 		id TEXT PRIMARY KEY, name TEXT, iata TEXT
@@ -203,14 +203,14 @@ func TestLoadNeighborEdgesFromDB(t *testing.T) {
 }
 
 func TestStoreObsResolvedPathInBroadcast(t *testing.T) {
-	// Verify resolved_path appears in broadcast maps
-	pk := "aabbccdd"
+	// After #800 refactor, resolved_path is no longer stored on StoreTx/StoreObs structs.
+	// Broadcast maps carry resolved_path from the decode-window, not from struct fields.
+	// This test verifies pickBestObservation no longer sets ResolvedPath on tx.
 	obs := &StoreObs{
 		ID:           1,
 		ObserverID:   "obs1",
 		ObserverName: "Observer 1",
 		PathJSON:     `["aa"]`,
-		ResolvedPath: []*string{&pk},
 		Timestamp:    "2024-01-01T00:00:00Z",
 	}
 
@@ -221,32 +221,26 @@ func TestStoreObsResolvedPathInBroadcast(t *testing.T) {
 	}
 	pickBestObservation(tx)
 
-	if tx.ResolvedPath == nil {
-		t.Fatal("expected ResolvedPath to be set on tx after pickBestObservation")
-	}
-	if *tx.ResolvedPath[0] != "aabbccdd" {
-		t.Errorf("expected resolved path to be aabbccdd, got %s", *tx.ResolvedPath[0])
+	// tx should NOT have a ResolvedPath field anymore (compile-time guard)
+	// Verify the best observation's fields are propagated correctly
+	if tx.ObserverID != "obs1" {
+		t.Errorf("expected ObserverID=obs1, got %s", tx.ObserverID)
 	}
 }
 
 func TestResolvedPathInTxToMap(t *testing.T) {
-	pk := "aabbccdd"
+	// After #800, txToMap no longer includes resolved_path from the struct.
+	// resolved_path is only available via on-demand SQL fetch (txToMapWithRP).
 	tx := &StoreTx{
-		ID:           1,
-		Hash:         "abc123",
-		PathJSON:     `["aa"]`,
-		ResolvedPath: []*string{&pk},
-		obsKeys:      make(map[string]bool),
+		ID:       1,
+		Hash:     "abc123",
+		PathJSON: `["aa"]`,
+		obsKeys:  make(map[string]bool),
 	}
 
 	m := txToMap(tx)
-	rp, ok := m["resolved_path"]
-	if !ok {
-		t.Fatal("resolved_path not in txToMap output")
-	}
-	rpSlice, ok := rp.([]*string)
-	if !ok || len(rpSlice) != 1 || *rpSlice[0] != "aabbccdd" {
-		t.Errorf("unexpected resolved_path: %v", rp)
+	if _, ok := m["resolved_path"]; ok {
+		t.Error("resolved_path should not be in txToMap output (removed in #800)")
 	}
 }
 
@@ -365,27 +359,21 @@ func TestLoadWithResolvedPath(t *testing.T) {
 		t.Fatalf("expected 1 observation, got %d", len(tx.Observations))
 	}
 
-	obs := tx.Observations[0]
-	if obs.ResolvedPath == nil {
-		t.Fatal("expected ResolvedPath to be loaded")
-	}
-	if len(obs.ResolvedPath) != 1 || *obs.ResolvedPath[0] != "aabbccdd" {
-		t.Errorf("unexpected ResolvedPath: %v", obs.ResolvedPath)
-	}
-
-	// Check that pickBestObservation propagated resolved_path to tx
-	if tx.ResolvedPath == nil || len(tx.ResolvedPath) != 1 {
-		t.Error("expected ResolvedPath to be propagated to tx")
+	// After #800, ResolvedPath is not stored on StoreObs struct.
+	// Instead, resolved pubkeys are in the membership index.
+	_ = tx.Observations[0] // obs exists
+	h := resolvedPubkeyHash("aabbccdd")
+	if len(store.resolvedPubkeyIndex[h]) != 1 {
+		t.Fatal("expected resolved pubkey to be indexed")
 	}
 }
 
 func TestResolvedPathInAPIResponse(t *testing.T) {
-	// Test that TransmissionResp properly marshals resolved_path
-	pk := "aabbccddee"
+	// After #800, TransmissionResp no longer has ResolvedPath field.
+	// resolved_path is included dynamically in map-based API responses.
 	resp := TransmissionResp{
-		ID:           1,
-		Hash:         "test",
-		ResolvedPath: []*string{&pk, nil},
+		ID:   1,
+		Hash: "test",
 	}
 
 	data, err := json.Marshal(resp)
@@ -396,19 +384,9 @@ func TestResolvedPathInAPIResponse(t *testing.T) {
 	var m map[string]interface{}
 	json.Unmarshal(data, &m)
 
-	rp, ok := m["resolved_path"]
-	if !ok {
-		t.Fatal("resolved_path missing from JSON")
-	}
-	rpArr, ok := rp.([]interface{})
-	if !ok || len(rpArr) != 2 {
-		t.Fatalf("unexpected resolved_path shape: %v", rp)
-	}
-	if rpArr[0] != "aabbccddee" {
-		t.Errorf("first element wrong: %v", rpArr[0])
-	}
-	if rpArr[1] != nil {
-		t.Errorf("second element should be null: %v", rpArr[1])
+	// resolved_path should NOT be in the marshaled JSON
+	if _, ok := m["resolved_path"]; ok {
+		t.Error("resolved_path should not be in TransmissionResp JSON (#800)")
 	}
 }
 

cmd/server/node_blacklist_test.go

@@ -0,0 +1,311 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gorilla/mux"
+)
+
+func TestConfigIsBlacklisted(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"AA", "BB", "cc"},
+	}
+
+	tests := []struct {
+		pubkey    string
+		want      bool
+	}{
+		{"AA", true},
+		{"aa", true},   // case-insensitive
+		{"BB", true},
+		{"CC", true},   // lowercase "cc" matches uppercase
+		{"DD", false},
+		{"", false},
+		{"AAB", false},
+	}
+
+	for _, tt := range tests {
+		got := cfg.IsBlacklisted(tt.pubkey)
+		if got != tt.want {
+			t.Errorf("IsBlacklisted(%q) = %v, want %v", tt.pubkey, got, tt.want)
+		}
+	}
+}
+
+func TestConfigIsBlacklistedEmpty(t *testing.T) {
+	cfg := &Config{}
+	if cfg.IsBlacklisted("anything") {
+		t.Error("empty blacklist should not match anything")
+	}
+	if cfg.IsBlacklisted("") {
+		t.Error("empty blacklist should not match empty string")
+	}
+}
+
+func TestConfigBlacklistWhitespace(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"  AA  ", "BB"},
+	}
+	if !cfg.IsBlacklisted("AA") {
+		t.Error("trimmed key should match")
+	}
+	if !cfg.IsBlacklisted("  AA  ") {
+		t.Error("whitespace-padded key should match after trimming")
+	}
+}
+
+func TestConfigBlacklistEmptyEntries(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"", "  ", "AA"},
+	}
+	if !cfg.IsBlacklisted("AA") {
+		t.Error("non-empty entry should match")
+	}
+	if cfg.IsBlacklisted("") {
+		t.Error("empty blacklist entry should not match empty pubkey")
+	}
+}
+
+func TestBlacklistFiltersHandleNodes(t *testing.T) {
+	db := setupTestDB(t)
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('goodnode', 'GoodNode', 'companion', datetime('now'))")
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('badnode', 'BadNode', 'companion', datetime('now'))")
+
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	srv := NewServer(db, cfg, NewHub())
+
+	req := httptest.NewRequest("GET", "/api/nodes?limit=50", nil)
+	w := httptest.NewRecorder()
+	srv.RegisterRoutes(setupTestRouter(srv))
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	var resp NodeListResponse
+	if err := json.Unmarshal(w.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+
+	for _, node := range resp.Nodes {
+		if pk, _ := node["public_key"].(string); pk == "badnode" {
+			t.Error("blacklisted node should not appear in nodes list")
+		}
+	}
+	if resp.Total == 0 {
+		t.Error("expected at least one non-blacklisted node")
+	}
+}
+
+func TestBlacklistFiltersNodeDetail(t *testing.T) {
+	db := setupTestDB(t)
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('badnode', 'BadNode', 'companion', datetime('now'))")
+
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	srv := NewServer(db, cfg, NewHub())
+
+	req := httptest.NewRequest("GET", "/api/nodes/badnode", nil)
+	w := httptest.NewRecorder()
+	srv.RegisterRoutes(setupTestRouter(srv))
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for blacklisted node, got %d", w.Code)
+	}
+}
+
+func TestBlacklistFiltersNodeSearch(t *testing.T) {
+	db := setupTestDB(t)
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('badnode', 'TrollNode', 'companion', datetime('now'))")
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('goodnode', 'GoodNode', 'companion', datetime('now'))")
+
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	srv := NewServer(db, cfg, NewHub())
+
+	req := httptest.NewRequest("GET", "/api/nodes/search?q=Troll", nil)
+	w := httptest.NewRecorder()
+	srv.RegisterRoutes(setupTestRouter(srv))
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var resp NodeSearchResponse
+	if err := json.Unmarshal(w.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+
+	for _, node := range resp.Nodes {
+		if pk, _ := node["public_key"].(string); pk == "badnode" {
+			t.Error("blacklisted node should not appear in search results")
+		}
+	}
+}
+
+func TestNoBlacklistPassesAll(t *testing.T) {
+	db := setupTestDB(t)
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('somenode', 'SomeNode', 'companion', datetime('now'))")
+
+	cfg := &Config{}
+	srv := NewServer(db, cfg, NewHub())
+
+	req := httptest.NewRequest("GET", "/api/nodes?limit=50", nil)
+	w := httptest.NewRecorder()
+	srv.RegisterRoutes(setupTestRouter(srv))
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+
+	var resp NodeListResponse
+	if err := json.Unmarshal(w.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+	if resp.Total == 0 {
+		t.Error("without blacklist, node should appear")
+	}
+}
+
+// setupTestRouter creates a mux.Router and registers server routes.
+func setupTestRouter(srv *Server) *mux.Router {
+	r := mux.NewRouter()
+	srv.RegisterRoutes(r)
+	srv.router = r
+	return r
+}
+func TestBlacklistFiltersNeighborGraph(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	db := setupTestDB(t)
+	srv := NewServer(db, cfg, NewHub())
+	srv.RegisterRoutes(setupTestRouter(srv))
+
+	req := httptest.NewRequest("GET", "/api/analytics/neighbor-graph", nil)
+	w := httptest.NewRecorder()
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	var resp map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+
+	// Check edges don't contain blacklisted node
+	if edges, ok := resp["edges"].([]interface{}); ok {
+		for _, e := range edges {
+			if edge, ok := e.(map[string]interface{}); ok {
+				if src, _ := edge["source"].(string); src == "badnode" {
+					t.Error("blacklisted node should not appear as edge source in neighbor graph")
+				}
+				if tgt, _ := edge["target"].(string); tgt == "badnode" {
+					t.Error("blacklisted node should not appear as edge target in neighbor graph")
+				}
+			}
+		}
+	}
+
+	// Check nodes list doesn't contain blacklisted node
+	if nodes, ok := resp["nodes"].([]interface{}); ok {
+		for _, n := range nodes {
+			if node, ok := n.(map[string]interface{}); ok {
+				if pk, _ := node["pubkey"].(string); pk == "badnode" {
+					t.Error("blacklisted node should not appear in neighbor graph nodes")
+				}
+			}
+		}
+	}
+}
+
+func TestBlacklistFiltersResolveHops(t *testing.T) {
+	db := setupTestDB(t)
+	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role, last_seen) VALUES ('badnode', 'BadNode', 'companion', datetime('now'))")
+
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	srv := NewServer(db, cfg, NewHub())
+	srv.RegisterRoutes(setupTestRouter(srv))
+
+	req := httptest.NewRequest("GET", "/api/resolve-hops?hops=badnode", nil)
+	w := httptest.NewRecorder()
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
+	}
+
+	var resp ResolveHopsResponse
+	if err := json.Unmarshal(w.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("failed to parse response: %v", err)
+	}
+
+	if hr, ok := resp.Resolved["badnode"]; ok {
+		for _, c := range hr.Candidates {
+			if c.Pubkey == "badnode" {
+				t.Error("blacklisted node should not appear as resolve-hops candidate")
+			}
+		}
+	}
+}
+
+func TestBlacklistFiltersSubpathDetail(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"badnode"},
+	}
+	db := setupTestDB(t)
+	srv := NewServer(db, cfg, NewHub())
+	srv.RegisterRoutes(setupTestRouter(srv))
+
+	req := httptest.NewRequest("GET", "/api/analytics/subpath-detail?hops=badnode,othernode", nil)
+	w := httptest.NewRecorder()
+	srv.router.ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Errorf("expected 404 for subpath-detail with blacklisted hop, got %d", w.Code)
+	}
+}
+
+func TestBlacklistConcurrentIsBlacklisted(t *testing.T) {
+	cfg := &Config{
+		NodeBlacklist: []string{"AA", "BB", "CC"},
+	}
+
+	errc := make(chan error, 100)
+	for i := 0; i < 100; i++ {
+		go func() {
+			for j := 0; j < 100; j++ {
+				cfg.IsBlacklisted("AA")
+				cfg.IsBlacklisted("BB")
+				cfg.IsBlacklisted("DD")
+			}
+		}()
+	}
+
+	// If sync.Once is wrong, this would panic or race.
+	// We can't run the race detector on ARM, but at least verify no panics.
+	done := false
+	for !done {
+		select {
+		case <-errc:
+			t.Error("concurrent IsBlacklisted panicked")
+		default:
+			done = true
+		}
+	}
+}

cmd/server/resolved_index.go

@@ -0,0 +1,475 @@
+package main
+
+// Lock ordering contract (MUST be followed everywhere):
+//
+//   s.mu  →  s.lruMu   (s.mu is the outer lock, lruMu is the inner lock)
+//
+// • Never acquire s.lruMu while holding s.mu.
+// • fetchResolvedPathForObs takes lruMu independently — callers under s.mu
+//   must NOT call it directly; instead collect IDs under s.mu, release, then
+//   do LRU ops under lruMu separately.
+// • The backfill path (backfillResolvedPathsAsync) follows this by collecting
+//   obsIDs to invalidate under s.mu, releasing it, then taking lruMu.
+
+import (
+	"database/sql"
+	"hash/fnv"
+	"log"
+	"strings"
+)
+
+// resolvedPubkeyHash computes a fast 64-bit hash for membership index keying.
+// Uses FNV-1a from stdlib — good distribution, no external dependency.
+func resolvedPubkeyHash(pk string) uint64 {
+	h := fnv.New64a()
+	h.Write([]byte(strings.ToLower(pk)))
+	return h.Sum64()
+}
+
+// addToResolvedPubkeyIndex adds a txID under each resolved pubkey hash.
+// Deduplicates both within a single call AND across calls — won't add the
+// same (hash, txID) pair twice even when called multiple times for the same tx.
+// Must be called under s.mu write lock.
+func (s *PacketStore) addToResolvedPubkeyIndex(txID int, resolvedPubkeys []string) {
+	if !s.useResolvedPathIndex {
+		return
+	}
+	seen := make(map[uint64]bool, len(resolvedPubkeys))
+	for _, pk := range resolvedPubkeys {
+		if pk == "" {
+			continue
+		}
+		h := resolvedPubkeyHash(pk)
+		if seen[h] {
+			continue
+		}
+		seen[h] = true
+
+		// Cross-call dedup: check if (h, txID) already exists in forward index.
+		existing := s.resolvedPubkeyIndex[h]
+		alreadyPresent := false
+		for _, id := range existing {
+			if id == txID {
+				alreadyPresent = true
+				break
+			}
+		}
+		if alreadyPresent {
+			continue
+		}
+
+		s.resolvedPubkeyIndex[h] = append(existing, txID)
+		s.resolvedPubkeyReverse[txID] = append(s.resolvedPubkeyReverse[txID], h)
+	}
+}
+
+// removeFromResolvedPubkeyIndex removes all index entries for a txID using the reverse map.
+// Must be called under s.mu write lock.
+func (s *PacketStore) removeFromResolvedPubkeyIndex(txID int) {
+	if !s.useResolvedPathIndex {
+		return
+	}
+	hashes := s.resolvedPubkeyReverse[txID]
+	for _, h := range hashes {
+		list := s.resolvedPubkeyIndex[h]
+		// Remove ALL occurrences of txID (not just the first) to prevent orphans.
+		filtered := list[:0]
+		for _, id := range list {
+			if id != txID {
+				filtered = append(filtered, id)
+			}
+		}
+		if len(filtered) == 0 {
+			delete(s.resolvedPubkeyIndex, h)
+		} else {
+			s.resolvedPubkeyIndex[h] = filtered
+		}
+	}
+	delete(s.resolvedPubkeyReverse, txID)
+}
+
+// extractResolvedPubkeys extracts all non-nil, non-empty pubkeys from a resolved path.
+func extractResolvedPubkeys(rp []*string) []string {
+	if len(rp) == 0 {
+		return nil
+	}
+	result := make([]string, 0, len(rp))
+	for _, p := range rp {
+		if p != nil && *p != "" {
+			result = append(result, *p)
+		}
+	}
+	return result
+}
+
+// mergeResolvedPubkeys collects unique non-empty pubkeys from multiple resolved paths.
+func mergeResolvedPubkeys(paths ...[]*string) []string {
+	seen := make(map[string]bool)
+	var result []string
+	for _, rp := range paths {
+		for _, p := range rp {
+			if p != nil && *p != "" && !seen[*p] {
+				seen[*p] = true
+				result = append(result, *p)
+			}
+		}
+	}
+	return result
+}
+
+// nodeInResolvedPathViaIndex checks whether a transmission is associated with
+// a target pubkey using the membership index + collision-safety SQL check.
+// Must be called under s.mu RLock at minimum.
+func (s *PacketStore) nodeInResolvedPathViaIndex(tx *StoreTx, targetPK string) bool {
+	if !s.useResolvedPathIndex {
+		// Flag off: can't disambiguate, keep candidate (conservative)
+		return true
+	}
+
+	// If this tx has no indexed pubkeys at all, we can't disambiguate —
+	// keep the candidate (same as old behavior for NULL resolved_path).
+	if _, hasReverse := s.resolvedPubkeyReverse[tx.ID]; !hasReverse {
+		return true
+	}
+
+	h := resolvedPubkeyHash(targetPK)
+	txIDs := s.resolvedPubkeyIndex[h]
+
+	// Check if this tx's ID is in the candidate list
+	for _, id := range txIDs {
+		if id == tx.ID {
+			// Found in index. Collision-safety: verify with SQL.
+			if s.db != nil && s.db.conn != nil {
+				return s.confirmResolvedPathContains(tx.ID, targetPK)
+			}
+			return true // no DB, trust the index
+		}
+	}
+
+	return false
+}
+
+// confirmResolvedPathContains verifies an exact pubkey match in resolved_path
+// via SQL. This is the collision-safety fallback for the membership index.
+func (s *PacketStore) confirmResolvedPathContains(txID int, pubkey string) bool {
+	if s.db == nil || s.db.conn == nil {
+		return true
+	}
+	// Use INSTR with surrounding quotes for exact match — avoids LIKE escape issues.
+	// resolved_path format: ["pubkey1","pubkey2",...]
+	needle := `"` + strings.ToLower(pubkey) + `"`
+	var count int
+	err := s.db.conn.QueryRow(
+		`SELECT COUNT(*) FROM observations WHERE transmission_id = ? AND INSTR(LOWER(resolved_path), ?) > 0`,
+		txID, needle,
+	).Scan(&count)
+	if err != nil {
+		return true // on error, keep the candidate
+	}
+	return count > 0
+}
+
+// fetchResolvedPathsForTx fetches resolved_path from SQLite for all observations
+// of a transmission. Used for on-demand API responses and eviction cleanup.
+func (s *PacketStore) fetchResolvedPathsForTx(txID int) map[int][]*string {
+	if s.db == nil || s.db.conn == nil {
+		return nil
+	}
+	rows, err := s.db.conn.Query(
+		`SELECT id, resolved_path FROM observations WHERE transmission_id = ? AND resolved_path IS NOT NULL`,
+		txID,
+	)
+	if err != nil {
+		return nil
+	}
+	defer rows.Close()
+
+	result := make(map[int][]*string)
+	for rows.Next() {
+		var obsID int
+		var rpJSON sql.NullString
+		if err := rows.Scan(&obsID, &rpJSON); err != nil {
+			continue
+		}
+		if rpJSON.Valid && rpJSON.String != "" {
+			result[obsID] = unmarshalResolvedPath(rpJSON.String)
+		}
+	}
+	return result
+}
+
+// fetchResolvedPathForObs fetches resolved_path for a single observation,
+// using the LRU cache.
+func (s *PacketStore) fetchResolvedPathForObs(obsID int) []*string {
+	if s.db == nil || s.db.conn == nil {
+		return nil
+	}
+
+	// Check LRU cache first
+	s.lruMu.RLock()
+	if s.apiResolvedPathLRU != nil {
+		if entry, ok := s.apiResolvedPathLRU[obsID]; ok {
+			s.lruMu.RUnlock()
+			return entry
+		}
+	}
+	s.lruMu.RUnlock()
+
+	var rpJSON sql.NullString
+	err := s.db.conn.QueryRow(
+		`SELECT resolved_path FROM observations WHERE id = ?`, obsID,
+	).Scan(&rpJSON)
+	if err != nil || !rpJSON.Valid {
+		return nil
+	}
+	rp := unmarshalResolvedPath(rpJSON.String)
+
+	// Store in LRU
+	s.lruMu.Lock()
+	s.lruPut(obsID, rp)
+	s.lruMu.Unlock()
+
+	return rp
+}
+
+// fetchResolvedPathForTxBest returns the best observation's resolved_path for a tx.
+//
+// "Best" = the longest path_json among observations that actually have a stored
+// resolved_path. Earlier versions picked the longest-path obs unconditionally
+// and queried SQL for that single ID — if the longest-path obs had NULL
+// resolved_path while a shorter sibling had one, the call returned nil and
+// callers (e.g. /api/nodes/{pk}/health.recentPackets) lost the field. Fixes
+// #810 by checking all observations and falling back to the longest sibling
+// that has a stored path.
+func (s *PacketStore) fetchResolvedPathForTxBest(tx *StoreTx) []*string {
+	if tx == nil || len(tx.Observations) == 0 {
+		return nil
+	}
+	// Fast path: try the longest-path obs first via the LRU/SQL helper.
+	longest := tx.Observations[0]
+	longestLen := pathLen(longest.PathJSON)
+	for _, obs := range tx.Observations[1:] {
+		if l := pathLen(obs.PathJSON); l > longestLen {
+			longest = obs
+			longestLen = l
+		}
+	}
+	if rp := s.fetchResolvedPathForObs(longest.ID); rp != nil {
+		return rp
+	}
+	// Fallback: longest-path obs has no stored resolved_path. Query all
+	// observations for this tx and pick the one with the longest path_json
+	// that actually has a stored resolved_path.
+	rpMap := s.fetchResolvedPathsForTx(tx.ID)
+	if len(rpMap) == 0 {
+		return nil
+	}
+	var bestRP []*string
+	bestObsID := 0
+	bestLen := -1
+	for _, obs := range tx.Observations {
+		rp, ok := rpMap[obs.ID]
+		if !ok || rp == nil {
+			continue
+		}
+		if l := pathLen(obs.PathJSON); l > bestLen {
+			bestLen = l
+			bestRP = rp
+			bestObsID = obs.ID
+		}
+	}
+	// Populate LRU so repeat lookups for this tx don't re-issue the multi-row
+	// SQL fallback (e.g. dashboard polling /api/nodes/{pk}/health).
+	if bestRP != nil && bestObsID != 0 {
+		s.lruMu.Lock()
+		s.lruPut(bestObsID, bestRP)
+		s.lruMu.Unlock()
+	}
+	return bestRP
+}
+
+// --- Simple LRU cache for resolved paths ---
+
+const lruMaxSize = 10000
+
+// lruPut adds an entry. Must be called under s.lruMu write lock.
+func (s *PacketStore) lruPut(obsID int, rp []*string) {
+	if s.apiResolvedPathLRU == nil {
+		return
+	}
+	if _, exists := s.apiResolvedPathLRU[obsID]; exists {
+		return
+	}
+	// Compact lruOrder if stale entries exceed 50% of capacity.
+	// This prevents effective capacity degradation after bulk deletions.
+	if len(s.lruOrder) >= lruMaxSize && len(s.apiResolvedPathLRU) < lruMaxSize/2 {
+		compacted := make([]int, 0, len(s.apiResolvedPathLRU))
+		for _, id := range s.lruOrder {
+			if _, ok := s.apiResolvedPathLRU[id]; ok {
+				compacted = append(compacted, id)
+			}
+		}
+		s.lruOrder = compacted
+	}
+	if len(s.lruOrder) >= lruMaxSize {
+		// Evict oldest, skipping stale entries
+		for len(s.lruOrder) > 0 {
+			evictID := s.lruOrder[0]
+			s.lruOrder = s.lruOrder[1:]
+			if _, ok := s.apiResolvedPathLRU[evictID]; ok {
+				delete(s.apiResolvedPathLRU, evictID)
+				break
+			}
+			// stale entry — skip and continue
+		}
+	}
+	s.apiResolvedPathLRU[obsID] = rp
+	s.lruOrder = append(s.lruOrder, obsID)
+}
+
+// lruDelete removes an entry. Must be called under s.lruMu write lock.
+func (s *PacketStore) lruDelete(obsID int) {
+	if s.apiResolvedPathLRU == nil {
+		return
+	}
+	delete(s.apiResolvedPathLRU, obsID)
+	// Don't scan lruOrder — eviction handles stale entries naturally.
+}
+
+// resolvedPubkeysForEvictionBatch fetches resolved pubkeys for multiple txIDs
+// from SQL in a single batched query. Returns a map from txID to unique pubkeys.
+// MUST be called WITHOUT holding s.mu — this is the whole point of the batch approach.
+// Chunks queries to stay under SQLite's 500-parameter limit.
+func (s *PacketStore) resolvedPubkeysForEvictionBatch(txIDs []int) map[int][]string {
+	result := make(map[int][]string, len(txIDs))
+	if len(txIDs) == 0 || s.db == nil || s.db.conn == nil {
+		return result
+	}
+
+	const chunkSize = 499 // SQLite SQLITE_MAX_VARIABLE_NUMBER default is 999; stay well under
+	for start := 0; start < len(txIDs); start += chunkSize {
+		end := start + chunkSize
+		if end > len(txIDs) {
+			end = len(txIDs)
+		}
+		chunk := txIDs[start:end]
+
+		// Build query with placeholders
+		placeholders := make([]byte, 0, len(chunk)*2)
+		args := make([]interface{}, len(chunk))
+		for i, id := range chunk {
+			if i > 0 {
+				placeholders = append(placeholders, ',')
+			}
+			placeholders = append(placeholders, '?')
+			args[i] = id
+		}
+
+		query := "SELECT transmission_id, resolved_path FROM observations WHERE transmission_id IN (" +
+			string(placeholders) + ") AND resolved_path IS NOT NULL"
+
+		rows, err := s.db.conn.Query(query, args...)
+		if err != nil {
+			continue
+		}
+
+		for rows.Next() {
+			var txID int
+			var rpJSON sql.NullString
+			if err := rows.Scan(&txID, &rpJSON); err != nil {
+				continue
+			}
+			if !rpJSON.Valid || rpJSON.String == "" {
+				continue
+			}
+			rp := unmarshalResolvedPath(rpJSON.String)
+			for _, p := range rp {
+				if p != nil && *p != "" {
+					result[txID] = append(result[txID], *p)
+				}
+			}
+		}
+		rows.Close()
+	}
+
+	// Deduplicate per-txID
+	for txID, pks := range result {
+		seen := make(map[string]bool, len(pks))
+		deduped := pks[:0]
+		for _, pk := range pks {
+			if !seen[pk] {
+				seen[pk] = true
+				deduped = append(deduped, pk)
+			}
+		}
+		result[txID] = deduped
+	}
+
+	return result
+}
+
+// initResolvedPathIndex initializes the resolved path index data structures.
+func (s *PacketStore) initResolvedPathIndex() {
+	s.resolvedPubkeyIndex = make(map[uint64][]int, 4096)
+	s.resolvedPubkeyReverse = make(map[int][]uint64, 4096)
+	s.apiResolvedPathLRU = make(map[int][]*string, lruMaxSize)
+	s.lruOrder = make([]int, 0, lruMaxSize)
+}
+
+// CompactResolvedPubkeyIndex reclaims memory from the resolved pubkey index maps
+// after eviction. It removes empty forward-index entries (shouldn't exist if
+// removeFromResolvedPubkeyIndex is correct, but defense in depth) and clips
+// oversized slice backing arrays where cap > 2*len.
+// Must be called under s.mu write lock.
+func (s *PacketStore) CompactResolvedPubkeyIndex() {
+	if !s.useResolvedPathIndex {
+		return
+	}
+	for h, ids := range s.resolvedPubkeyIndex {
+		if len(ids) == 0 {
+			delete(s.resolvedPubkeyIndex, h)
+			continue
+		}
+		// Clip oversized backing arrays: if cap > 2*len, reallocate.
+		if cap(ids) > 2*len(ids)+8 {
+			clipped := make([]int, len(ids))
+			copy(clipped, ids)
+			s.resolvedPubkeyIndex[h] = clipped
+		}
+	}
+	for txID, hashes := range s.resolvedPubkeyReverse {
+		if len(hashes) == 0 {
+			delete(s.resolvedPubkeyReverse, txID)
+			continue
+		}
+		if cap(hashes) > 2*len(hashes)+8 {
+			clipped := make([]uint64, len(hashes))
+			copy(clipped, hashes)
+			s.resolvedPubkeyReverse[txID] = clipped
+		}
+	}
+}
+
+// defaultMaxResolvedPubkeyIndexEntries is the default hard cap for the forward
+// index. When exceeded, a warning is logged. No auto-eviction — that's the
+// eviction ticker's job.
+const defaultMaxResolvedPubkeyIndexEntries = 5_000_000
+
+// CheckResolvedPubkeyIndexSize logs a warning if the resolved pubkey forward
+// index exceeds the configured maximum entries. Must be called under s.mu
+// read lock at minimum.
+func (s *PacketStore) CheckResolvedPubkeyIndexSize() {
+	if !s.useResolvedPathIndex {
+		return
+	}
+	maxEntries := s.maxResolvedPubkeyIndexEntries
+	if maxEntries <= 0 {
+		maxEntries = defaultMaxResolvedPubkeyIndexEntries
+	}
+	fwdLen := len(s.resolvedPubkeyIndex)
+	revLen := len(s.resolvedPubkeyReverse)
+	if fwdLen > maxEntries || revLen > maxEntries {
+		log.Printf("[store] WARNING: resolvedPubkeyIndex size exceeds limit — forward=%d reverse=%d limit=%d",
+			fwdLen, revLen, maxEntries)
+	}
+}

cmd/server/routes.go

@@ -124,6 +124,7 @@ func (s *Server) RegisterRoutes(r *mux.Router) {
 	r.Handle("/api/perf/reset", s.requireAPIKey(http.HandlerFunc(s.handlePerfReset))).Methods("POST")
 	r.Handle("/api/admin/prune", s.requireAPIKey(http.HandlerFunc(s.handleAdminPrune))).Methods("POST")
 	r.Handle("/api/debug/affinity", s.requireAPIKey(http.HandlerFunc(s.handleDebugAffinity))).Methods("GET")
+	r.Handle("/api/dropped-packets", s.requireAPIKey(http.HandlerFunc(s.handleDroppedPackets))).Methods("GET")
 
 	// Packet endpoints
 	r.HandleFunc("/api/packets/observations", s.handleBatchObservations).Methods("POST")
@@ -142,6 +143,9 @@ func (s *Server) RegisterRoutes(r *mux.Router) {
 	r.HandleFunc("/api/nodes/{pubkey}/health", s.handleNodeHealth).Methods("GET")
 	r.HandleFunc("/api/nodes/{pubkey}/paths", s.handleNodePaths).Methods("GET")
 	r.HandleFunc("/api/nodes/{pubkey}/analytics", s.handleNodeAnalytics).Methods("GET")
+	r.HandleFunc("/api/nodes/clock-skew", s.handleFleetClockSkew).Methods("GET")
+	r.HandleFunc("/api/nodes/{pubkey}/clock-skew", s.handleNodeClockSkew).Methods("GET")
+	r.HandleFunc("/api/observers/clock-skew", s.handleObserverClockSkew).Methods("GET")
 	r.HandleFunc("/api/nodes/{pubkey}/neighbors", s.handleNodeNeighbors).Methods("GET")
 	r.HandleFunc("/api/nodes/{pubkey}", s.handleNodeDetail).Methods("GET")
 	r.HandleFunc("/api/nodes", s.handleNodes).Methods("GET")
@@ -565,6 +569,16 @@ func (s *Server) handleStats(w http.ResponseWriter, r *http.Request) {
 		backfillProgress = 1
 	}
 
+	// Memory accounting (#832). storeDataMB is the in-store packet byte
+	// estimate (the old "trackedMB"); processRSSMB / goHeapInuseMB / goSysMB
+	// give ops the breakdown needed to reason about real RSS. All values
+	// share a single 1s-cached snapshot to amortize ReadMemStats cost.
+	var storeDataMB float64
+	if s.store != nil {
+		storeDataMB = s.store.trackedMemoryMB()
+	}
+	mem := s.getMemorySnapshot(storeDataMB)
+
 	resp := &StatsResponse{
 		TotalPackets:       stats.TotalPackets,
 		TotalTransmissions: &stats.TotalTransmissions,
@@ -584,8 +598,16 @@ func (s *Server) handleStats(w http.ResponseWriter, r *http.Request) {
 			Companions: counts["companions"],
 			Sensors:    counts["sensors"],
 		},
-		Backfilling:      backfilling,
-		BackfillProgress: backfillProgress,
+		Backfilling:           backfilling,
+		BackfillProgress:      backfillProgress,
+		SignatureDrops:        s.db.GetSignatureDropCount(),
+		HashMigrationComplete: s.store != nil && s.store.hashMigrationComplete.Load(),
+
+		TrackedMB:     mem.StoreDataMB, // deprecated alias
+		StoreDataMB:   mem.StoreDataMB,
+		ProcessRSSMB:  mem.ProcessRSSMB,
+		GoHeapInuseMB: mem.GoHeapInuseMB,
+		GoSysMB:       mem.GoSysMB,
 	}
 
 	s.statsMu.Lock()
@@ -768,6 +790,7 @@ func (s *Server) handlePackets(w http.ResponseWriter, r *http.Request) {
 		Until:    r.URL.Query().Get("until"),
 		Region:   r.URL.Query().Get("region"),
 		Node:     r.URL.Query().Get("node"),
+		Channel:  r.URL.Query().Get("channel"),
 		Order:              "DESC",
 		ExpandObservations: r.URL.Query().Get("expand") == "observations",
 	}
@@ -870,9 +893,11 @@ func (s *Server) handleBatchObservations(w http.ResponseWriter, r *http.Request)
 func (s *Server) handlePacketDetail(w http.ResponseWriter, r *http.Request) {
 	param := mux.Vars(r)["id"]
 	var packet map[string]interface{}
+	fromDB := false
 
+	isHash := hashPattern.MatchString(strings.ToLower(param))
 	if s.store != nil {
-		if hashPattern.MatchString(strings.ToLower(param)) {
+		if isHash {
 			packet = s.store.GetPacketByHash(param)
 		}
 		if packet == nil {
@@ -885,6 +910,25 @@ func (s *Server) handlePacketDetail(w http.ResponseWriter, r *http.Request) {
 			}
 		}
 	}
+	// DB fallback: in-memory PacketStore prunes old entries, but the SQLite
+	// DB retains them and is the source for /api/nodes recentAdverts. Without
+	// this fallback, links from node-detail pages 404 once the packet ages out.
+	if packet == nil && s.db != nil {
+		if isHash {
+			if dbPkt, err := s.db.GetPacketByHash(param); err == nil && dbPkt != nil {
+				packet = dbPkt
+				fromDB = true
+			}
+		}
+		if packet == nil {
+			if id, parseErr := strconv.Atoi(param); parseErr == nil {
+				if dbPkt, err := s.db.GetTransmissionByID(id); err == nil && dbPkt != nil {
+					packet = dbPkt
+					fromDB = true
+				}
+			}
+		}
+	}
 	if packet == nil {
 		writeError(w, 404, "Not found")
 		return
@@ -895,6 +939,9 @@ func (s *Server) handlePacketDetail(w http.ResponseWriter, r *http.Request) {
 	if s.store != nil {
 		observations = s.store.GetObservationsForHash(hash)
 	}
+	if len(observations) == 0 && fromDB && s.db != nil && hash != "" {
+		observations = s.db.GetObservationsForHash(hash)
+	}
 	observationCount := len(observations)
 	if observationCount == 0 {
 		observationCount = 1
@@ -1048,6 +1095,17 @@ func (s *Server) handleNodes(w http.ResponseWriter, r *http.Request) {
 		total = len(filtered)
 		nodes = filtered
 	}
+	// Filter blacklisted nodes
+	if len(s.cfg.NodeBlacklist) > 0 {
+		filtered := nodes[:0]
+		for _, node := range nodes {
+			if pk, ok := node["public_key"].(string); !ok || !s.cfg.IsBlacklisted(pk) {
+				filtered = append(filtered, node)
+			}
+		}
+		total = len(filtered)
+		nodes = filtered
+	}
 	writeJSON(w, NodeListResponse{Nodes: nodes, Total: total, Counts: counts})
 }
 
@@ -1062,11 +1120,25 @@ func (s *Server) handleNodeSearch(w http.ResponseWriter, r *http.Request) {
 		writeError(w, 500, err.Error())
 		return
 	}
+	// Filter blacklisted nodes from search results
+	if len(s.cfg.NodeBlacklist) > 0 {
+		filtered := make([]map[string]interface{}, 0, len(nodes))
+		for _, node := range nodes {
+			if pk, ok := node["public_key"].(string); !ok || !s.cfg.IsBlacklisted(pk) {
+				filtered = append(filtered, node)
+			}
+		}
+		nodes = filtered
+	}
 	writeJSON(w, NodeSearchResponse{Nodes: nodes})
 }
 
 func (s *Server) handleNodeDetail(w http.ResponseWriter, r *http.Request) {
 	pubkey := mux.Vars(r)["pubkey"]
+	if s.cfg.IsBlacklisted(pubkey) {
+		writeError(w, 404, "Not found")
+		return
+	}
 	node, err := s.db.GetNodeByPubkey(pubkey)
 	if err != nil || node == nil {
 		writeError(w, 404, "Not found")
@@ -1092,6 +1164,10 @@ func (s *Server) handleNodeDetail(w http.ResponseWriter, r *http.Request) {
 
 func (s *Server) handleNodeHealth(w http.ResponseWriter, r *http.Request) {
 	pubkey := mux.Vars(r)["pubkey"]
+	if s.cfg.IsBlacklisted(pubkey) {
+		writeError(w, 404, "Not found")
+		return
+	}
 	if s.store != nil {
 		result, err := s.store.GetNodeHealth(pubkey)
 		if err != nil || result == nil {
@@ -1112,7 +1188,19 @@ func (s *Server) handleBulkHealth(w http.ResponseWriter, r *http.Request) {
 
 	if s.store != nil {
 		region := r.URL.Query().Get("region")
-		writeJSON(w, s.store.GetBulkHealth(limit, region))
+		results := s.store.GetBulkHealth(limit, region)
+		// Filter blacklisted nodes
+		if len(s.cfg.NodeBlacklist) > 0 {
+			filtered := make([]map[string]interface{}, 0, len(results))
+			for _, entry := range results {
+				if pk, ok := entry["public_key"].(string); !ok || !s.cfg.IsBlacklisted(pk) {
+					filtered = append(filtered, entry)
+				}
+			}
+			writeJSON(w, filtered)
+			return
+		}
+		writeJSON(w, results)
 		return
 	}
 
@@ -1131,6 +1219,10 @@ func (s *Server) handleNetworkStatus(w http.ResponseWriter, r *http.Request) {
 
 func (s *Server) handleNodePaths(w http.ResponseWriter, r *http.Request) {
 	pubkey := mux.Vars(r)["pubkey"]
+	if s.cfg.IsBlacklisted(pubkey) {
+		writeError(w, 404, "Not found")
+		return
+	}
 	node, err := s.db.GetNodeByPubkey(pubkey)
 	if err != nil || node == nil {
 		writeError(w, 404, "Not found")
@@ -1182,14 +1274,52 @@ func (s *Server) handleNodePaths(w http.ResponseWriter, r *http.Request) {
 	// Post-filter: verify target node actually appears in each candidate's resolved_path.
 	// The byPathHop index uses short prefixes which can collide (e.g. "c0" matches multiple nodes).
 	// We lean on resolved_path (from neighbor affinity graph) to disambiguate.
-	filtered := candidates[:0] // reuse backing array
-	for _, tx := range candidates {
-		if nodeInResolvedPath(tx, lowerPK) {
-			filtered = append(filtered, tx)
+	//
+	// Collect candidate IDs and index membership under the read lock, then release
+	// the lock before running SQL queries (confirmResolvedPathContains does disk I/O).
+	type candidateCheck struct {
+		tx         *StoreTx
+		hasReverse bool
+		inIndex    bool
+	}
+	checks := make([]candidateCheck, len(candidates))
+	for i, tx := range candidates {
+		cc := candidateCheck{tx: tx}
+		if !s.store.useResolvedPathIndex {
+			cc.inIndex = true // flag off — keep all
+		} else if _, hasRev := s.store.resolvedPubkeyReverse[tx.ID]; !hasRev {
+			cc.inIndex = true // no indexed pubkeys — keep (conservative)
+		} else {
+			h := resolvedPubkeyHash(lowerPK)
+			for _, id := range s.store.resolvedPubkeyIndex[h] {
+				if id == tx.ID {
+					cc.hasReverse = true // needs SQL confirmation
+					break
+				}
+			}
+			// If not in index at all, it's a definite no
 		}
+		checks[i] = cc
+	}
+	s.store.mu.RUnlock()
+
+	// Now run SQL checks outside the lock for candidates that need confirmation.
+	filtered := candidates[:0]
+	for _, cc := range checks {
+		if cc.inIndex {
+			filtered = append(filtered, cc.tx)
+		} else if cc.hasReverse {
+			if s.store.confirmResolvedPathContains(cc.tx.ID, lowerPK) {
+				filtered = append(filtered, cc.tx)
+			}
+		}
+		// else: not in index → exclude
 	}
 	candidates = filtered
 
+	// Re-acquire read lock for the aggregation phase that reads store data.
+	s.store.mu.RLock()
+
 	type pathAgg struct {
 		Hops       []PathHopResp
 		Count      int
@@ -1294,6 +1424,10 @@ func (s *Server) handleNodePaths(w http.ResponseWriter, r *http.Request) {
 
 func (s *Server) handleNodeAnalytics(w http.ResponseWriter, r *http.Request) {
 	pubkey := mux.Vars(r)["pubkey"]
+	if s.cfg.IsBlacklisted(pubkey) {
+		writeError(w, 404, "Not found")
+		return
+	}
 	days := queryInt(r, "days", 7)
 	if days < 1 {
 		days = 1
@@ -1315,6 +1449,36 @@ func (s *Server) handleNodeAnalytics(w http.ResponseWriter, r *http.Request) {
 	writeError(w, 404, "Not found")
 }
 
+func (s *Server) handleNodeClockSkew(w http.ResponseWriter, r *http.Request) {
+	pubkey := mux.Vars(r)["pubkey"]
+	if s.store == nil {
+		writeError(w, 404, "Not found")
+		return
+	}
+	result := s.store.GetNodeClockSkew(pubkey)
+	if result == nil {
+		writeError(w, 404, "No clock skew data for this node")
+		return
+	}
+	writeJSON(w, result)
+}
+
+func (s *Server) handleObserverClockSkew(w http.ResponseWriter, r *http.Request) {
+	if s.store == nil {
+		writeJSON(w, []ObserverCalibration{})
+		return
+	}
+	writeJSON(w, s.store.GetObserverCalibrations())
+}
+
+func (s *Server) handleFleetClockSkew(w http.ResponseWriter, r *http.Request) {
+	if s.store == nil {
+		writeJSON(w, []*NodeClockSkew{})
+		return
+	}
+	writeJSON(w, s.store.GetFleetClockSkew())
+}
+
 // --- Analytics Handlers ---
 
 func (s *Server) handleAnalyticsRF(w http.ResponseWriter, r *http.Request) {
@@ -1340,7 +1504,11 @@ func (s *Server) handleAnalyticsRF(w http.ResponseWriter, r *http.Request) {
 func (s *Server) handleAnalyticsTopology(w http.ResponseWriter, r *http.Request) {
 	region := r.URL.Query().Get("region")
 	if s.store != nil {
-		writeJSON(w, s.store.GetAnalyticsTopology(region))
+		data := s.store.GetAnalyticsTopology(region)
+		if s.cfg != nil && len(s.cfg.NodeBlacklist) > 0 {
+			data = s.filterBlacklistedFromTopology(data)
+		}
+		writeJSON(w, data)
 		return
 	}
 	writeJSON(w, TopologyResponse{
@@ -1428,7 +1596,11 @@ func (s *Server) handleAnalyticsSubpaths(w http.ResponseWriter, r *http.Request)
 		}
 		maxLen := queryInt(r, "maxLen", 8)
 		limit := queryInt(r, "limit", 100)
-		writeJSON(w, s.store.GetAnalyticsSubpaths(region, minLen, maxLen, limit))
+		data := s.store.GetAnalyticsSubpaths(region, minLen, maxLen, limit)
+		if s.cfg != nil && len(s.cfg.NodeBlacklist) > 0 {
+			data = s.filterBlacklistedFromSubpaths(data)
+		}
+		writeJSON(w, data)
 		return
 	}
 	writeJSON(w, SubpathsResponse{
@@ -1480,6 +1652,11 @@ func (s *Server) handleAnalyticsSubpathsBulk(w http.ResponseWriter, r *http.Requ
 	}
 
 	results := s.store.GetAnalyticsSubpathsBulk(region, groups)
+	if s.cfg != nil && len(s.cfg.NodeBlacklist) > 0 {
+		for i, r := range results {
+			results[i] = s.filterBlacklistedFromSubpaths(r)
+		}
+	}
 	writeJSON(w, map[string]interface{}{"results": results})
 }
 
@@ -1499,6 +1676,15 @@ func (s *Server) handleAnalyticsSubpathDetail(w http.ResponseWriter, r *http.Req
 		writeJSON(w, ErrorResp{Error: "Need at least 2 hops"})
 		return
 	}
+	// Reject if any hop is a blacklisted node.
+	if s.cfg != nil && len(s.cfg.NodeBlacklist) > 0 {
+		for _, hop := range rawHops {
+			if s.cfg.IsBlacklisted(hop) {
+				writeError(w, 404, "Not found")
+				return
+			}
+		}
+	}
 	if s.store != nil {
 		writeJSON(w, s.store.GetSubpathDetail(rawHops))
 		return
@@ -1564,6 +1750,10 @@ func (s *Server) handleResolveHops(w http.ResponseWriter, r *http.Request) {
 		if pm != nil {
 			if matched, ok := pm.m[hopLower]; ok {
 				for _, ni := range matched {
+					// Skip blacklisted nodes from resolution results.
+					if s.cfg != nil && s.cfg.IsBlacklisted(ni.PublicKey) {
+						continue
+					}
 					c := HopCandidate{Pubkey: ni.PublicKey}
 					if ni.Name != "" {
 						c.Name = ni.Name
@@ -1632,7 +1822,8 @@ func (s *Server) handleResolveHops(w http.ResponseWriter, r *http.Request) {
 			}
 
 			// Use the resolved node as the default (best-effort pick).
-			if best != nil {
+			// Skip if the best pick is a blacklisted node.
+			if best != nil && !(s.cfg != nil && s.cfg.IsBlacklisted(best.PublicKey)) {
 				hr.Name = best.Name
 				hr.Pubkey = best.PublicKey
 			}
@@ -1655,18 +1846,35 @@ func (s *Server) handleResolveHops(w http.ResponseWriter, r *http.Request) {
 }
 
 func (s *Server) handleChannels(w http.ResponseWriter, r *http.Request) {
-	if s.store != nil {
-		region := r.URL.Query().Get("region")
-		channels := s.store.GetChannels(region)
+	region := r.URL.Query().Get("region")
+	includeEncrypted := r.URL.Query().Get("includeEncrypted") == "true"
+	// Prefer DB for full history (in-memory store has limited retention)
+	if s.db != nil {
+		channels, err := s.db.GetChannels(region)
+		if err != nil {
+			writeError(w, 500, err.Error())
+			return
+		}
+		if includeEncrypted {
+			encrypted, err := s.db.GetEncryptedChannels(region)
+			if err != nil {
+				log.Printf("WARN GetEncryptedChannels: %v", err)
+			} else {
+				channels = append(channels, encrypted...)
+			}
+		}
 		writeJSON(w, ChannelListResponse{Channels: channels})
 		return
 	}
-	channels, err := s.db.GetChannels()
-	if err != nil {
-		writeError(w, 500, err.Error())
+	if s.store != nil {
+		channels := s.store.GetChannels(region)
+		if includeEncrypted {
+			channels = append(channels, s.store.GetEncryptedChannels(region)...)
+		}
+		writeJSON(w, ChannelListResponse{Channels: channels})
 		return
 	}
-	writeJSON(w, ChannelListResponse{Channels: channels})
+	writeJSON(w, ChannelListResponse{Channels: []map[string]interface{}{}})
 }
 
 func (s *Server) handleChannelMessages(w http.ResponseWriter, r *http.Request) {
@@ -1674,17 +1882,22 @@ func (s *Server) handleChannelMessages(w http.ResponseWriter, r *http.Request) {
 	limit := queryInt(r, "limit", 100)
 	offset := queryInt(r, "offset", 0)
 	region := r.URL.Query().Get("region")
+	// Prefer DB for full history (in-memory store has limited retention)
+	if s.db != nil {
+		messages, total, err := s.db.GetChannelMessages(hash, limit, offset, region)
+		if err != nil {
+			writeError(w, 500, err.Error())
+			return
+		}
+		writeJSON(w, ChannelMessagesResponse{Messages: messages, Total: total})
+		return
+	}
 	if s.store != nil {
 		messages, total := s.store.GetChannelMessages(hash, limit, offset, region)
 		writeJSON(w, ChannelMessagesResponse{Messages: messages, Total: total})
 		return
 	}
-	messages, total, err := s.db.GetChannelMessages(hash, limit, offset, region)
-	if err != nil {
-		writeError(w, 500, err.Error())
-		return
-	}
-	writeJSON(w, ChannelMessagesResponse{Messages: messages, Total: total})
+	writeJSON(w, ChannelMessagesResponse{Messages: []map[string]interface{}{}, Total: 0})
 }
 
 func (s *Server) handleObservers(w http.ResponseWriter, r *http.Request) {
@@ -1870,7 +2083,7 @@ func (s *Server) handleObserverAnalytics(w http.ResponseWriter, r *http.Request)
 			}
 			snrBuckets[bucket].Count++
 		}
-		if i < 20 {
+		if i < 20 && enriched["hash"] != nil {
 			recentPackets = append(recentPackets, enriched)
 		}
 	}
@@ -2153,9 +2366,6 @@ func mapSliceToTransmissions(maps []map[string]interface{}) []TransmissionResp {
 		tx.PathJSON = m["path_json"]
 		tx.Direction = m["direction"]
 		tx.Score = m["score"]
-		if rp, ok := m["resolved_path"].([]*string); ok {
-			tx.ResolvedPath = rp
-		}
 		result = append(result, tx)
 	}
 	return result
@@ -2176,10 +2386,10 @@ func mapSliceToObservations(maps []map[string]interface{}) []ObservationResp {
 		obs.SNR = m["snr"]
 		obs.RSSI = m["rssi"]
 		obs.PathJSON = m["path_json"]
+		obs.ResolvedPath = m["resolved_path"]
+		obs.Direction = m["direction"]
+		obs.RawHex = m["raw_hex"]
 		obs.Timestamp = m["timestamp"]
-		if rp, ok := m["resolved_path"].([]*string); ok {
-			obs.ResolvedPath = rp
-		}
 		result = append(result, obs)
 	}
 	return result
@@ -2330,16 +2540,167 @@ func (s *Server) handleAdminPrune(w http.ResponseWriter, r *http.Request) {
 		writeError(w, 400, "days parameter required (or set retention.packetDays in config)")
 		return
 	}
+
+	results := map[string]interface{}{}
+
+	// Prune old packets
 	n, err := s.db.PruneOldPackets(days)
 	if err != nil {
 		writeError(w, 500, err.Error())
 		return
 	}
 	log.Printf("[prune] deleted %d transmissions older than %d days", n, days)
-	writeJSON(w, map[string]interface{}{"deleted": n, "days": days})
+	results["packets_deleted"] = n
+	results["deleted"] = n // legacy alias
+
+	// Also mark stale observers as inactive if observerDays is configured
+	observerDays := s.cfg.ObserverDaysOrDefault()
+	if observerDays > 0 {
+		obsN, obsErr := s.db.RemoveStaleObservers(observerDays)
+		if obsErr != nil {
+			log.Printf("[prune] observer prune error: %v", obsErr)
+		} else {
+			results["observers_inactive"] = obsN
+		}
+	}
+
+	results["days"] = days
+	writeJSON(w, results)
 }
 
 // constantTimeEqual compares two strings in constant time to prevent timing attacks.
 func constantTimeEqual(a, b string) bool {
 	return subtle.ConstantTimeCompare([]byte(a), []byte(b)) == 1
 }
+
+// filterBlacklistedFromTopology removes blacklisted node references from the
+// topology analytics response (TopRepeaters, TopPairs, BestPathList, MultiObsNodes, PerObserverReach).
+func (s *Server) filterBlacklistedFromTopology(data map[string]interface{}) map[string]interface{} {
+	// Filter TopRepeaters
+	if repeaters, ok := data["topRepeaters"]; ok {
+		if arr, ok := repeaters.([]TopRepeater); ok {
+			var filtered []TopRepeater
+			for _, r := range arr {
+				if pk, ok := r.Pubkey.(string); ok && s.cfg.IsBlacklisted(pk) {
+					continue
+				}
+				filtered = append(filtered, r)
+			}
+			data["topRepeaters"] = filtered
+		}
+	}
+
+	// Filter TopPairs
+	if pairs, ok := data["topPairs"]; ok {
+		if arr, ok := pairs.([]TopPair); ok {
+			var filtered []TopPair
+			for _, p := range arr {
+				if pkA, ok := p.PubkeyA.(string); ok && s.cfg.IsBlacklisted(pkA) {
+					continue
+				}
+				if pkB, ok := p.PubkeyB.(string); ok && s.cfg.IsBlacklisted(pkB) {
+					continue
+				}
+				filtered = append(filtered, p)
+			}
+			data["topPairs"] = filtered
+		}
+	}
+
+	// Filter BestPathList
+	if paths, ok := data["bestPathList"]; ok {
+		if arr, ok := paths.([]BestPathEntry); ok {
+			var filtered []BestPathEntry
+			for _, p := range arr {
+				if pk, ok := p.Pubkey.(string); ok && s.cfg.IsBlacklisted(pk) {
+					continue
+				}
+				filtered = append(filtered, p)
+			}
+			data["bestPathList"] = filtered
+		}
+	}
+
+	// Filter MultiObsNodes
+	if nodes, ok := data["multiObsNodes"]; ok {
+		if arr, ok := nodes.([]MultiObsNode); ok {
+			var filtered []MultiObsNode
+			for _, n := range arr {
+				if pk, ok := n.Pubkey.(string); ok && s.cfg.IsBlacklisted(pk) {
+					continue
+				}
+				filtered = append(filtered, n)
+			}
+			data["multiObsNodes"] = filtered
+		}
+	}
+
+	// Filter PerObserverReach
+	if reach, ok := data["perObserverReach"]; ok {
+		if m, ok := reach.(map[string]*ObserverReach); ok {
+			for k, v := range m {
+				for ri := range v.Rings {
+					var filteredNodes []ReachNode
+					for _, rn := range v.Rings[ri].Nodes {
+						if pk, ok := rn.Pubkey.(string); ok && s.cfg.IsBlacklisted(pk) {
+							continue
+						}
+						filteredNodes = append(filteredNodes, rn)
+					}
+					v.Rings[ri].Nodes = filteredNodes
+				}
+				m[k] = v
+			}
+		}
+	}
+
+	return data
+}
+
+// filterBlacklistedFromSubpaths removes blacklisted node references from
+// the subpaths analytics response.
+func (s *Server) filterBlacklistedFromSubpaths(data map[string]interface{}) map[string]interface{} {
+	if subpaths, ok := data["subpaths"]; ok {
+		if arr, ok := subpaths.([]interface{}); ok {
+			var filtered []interface{}
+			for _, item := range arr {
+				if m, ok := item.(map[string]interface{}); ok {
+					if hops, ok := m["hops"].([]interface{}); ok {
+						skip := false
+						for _, h := range hops {
+							if hp, ok := h.(string); ok && s.cfg.IsBlacklisted(hp) {
+								skip = true
+								break
+							}
+						}
+						if skip {
+							continue
+						}
+					}
+				}
+				filtered = append(filtered, item)
+			}
+			data["subpaths"] = filtered
+		}
+	}
+	return data
+}
+
+// handleDroppedPackets returns recently dropped packets for investigation.
+func (s *Server) handleDroppedPackets(w http.ResponseWriter, r *http.Request) {
+	limit := 100
+	if v := r.URL.Query().Get("limit"); v != "" {
+		if n, err := strconv.Atoi(v); err == nil && n > 0 {
+			limit = n
+		}
+	}
+	observerID := r.URL.Query().Get("observer")
+	nodePubkey := r.URL.Query().Get("pubkey")
+
+	results, err := s.db.GetDroppedPackets(limit, observerID, nodePubkey)
+	if err != nil {
+		writeError(w, 500, err.Error())
+		return
+	}
+	writeJSON(w, results)
+}

cmd/server/routes_test.go

@@ -2219,8 +2219,8 @@ pk := "abcdef1234567890abcdef1234567890abcdef1234567890abcdef1234567890"
 db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role) VALUES (?, 'TestNode', 'repeater')", pk)
 
 decoded := `{"name":"TestNode","pubKey":"` + pk + `"}`
-raw1 := "04" + "00" + "aabb"
-raw2 := "04" + "40" + "aabb"
+raw1 := "11" + "01" + "aabb"
+raw2 := "11" + "41" + "aabb"
 
 payloadType := 4
 for i := 0; i < 3; i++ {
@@ -2267,8 +2267,8 @@ pk := "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"
 db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role) VALUES (?, 'Repeater2B', 'repeater')", pk)
 
 decoded := `{"name":"Repeater2B","pubKey":"` + pk + `"}`
-raw1byte := "04" + "00" + "aabb" // pathByte=0x00 → hashSize=1 (direct send, no hops)
-raw2byte := "04" + "40" + "aabb" // pathByte=0x40 → hashSize=2
+raw1byte := "11" + "01" + "aabb" // FLOOD, pathByte=0x01 → hashSize=1
+raw2byte := "11" + "41" + "aabb" // FLOOD, pathByte=0x41 → hashSize=2
 
 payloadType := 4
 // 1 packet with hashSize=1, 4 packets with hashSize=2 (latest is 2-byte)
@@ -2310,8 +2310,8 @@ func TestGetNodeHashSizeInfoLatestWins(t *testing.T) {
 	db.conn.Exec("INSERT OR IGNORE INTO nodes (public_key, name, role) VALUES (?, 'LatestWins', 'repeater')", pk)
 
 	decoded := `{"name":"LatestWins","pubKey":"` + pk + `"}`
-	raw1byte := "04" + "00" + "aabb" // pathByte=0x00 → hashSize=1
-	raw2byte := "04" + "40" + "aabb" // pathByte=0x40 → hashSize=2
+	raw1byte := "11" + "01" + "aabb" // FLOOD, pathByte=0x01 → hashSize=1
+	raw2byte := "11" + "41" + "aabb" // FLOOD, pathByte=0x41 → hashSize=2
 
 	payloadType := 4
 	// 4 historical 1-byte adverts, then 1 recent 2-byte advert (latest).
@@ -3681,67 +3681,55 @@ func TestNodePathsPrefixCollisionFilter(t *testing.T) {
 func TestNodeInResolvedPath(t *testing.T) {
 	target := "aabbccdd11223344"
 
-	// Case 1: tx.ResolvedPath contains target
-	pk := "aabbccdd11223344"
-	tx1 := &StoreTx{ResolvedPath: []*string{&pk}}
-	if !nodeInResolvedPath(tx1, target) {
-		t.Error("should match when ResolvedPath contains target")
+	// After #800, nodeInResolvedPath is replaced by nodeInResolvedPathViaIndex
+	// which uses the membership index. Test the index-based approach.
+	store := &PacketStore{
+		byNode:               make(map[string][]*StoreTx),
+		nodeHashes:           make(map[string]map[string]bool),
+		useResolvedPathIndex: true,
+	}
+	store.initResolvedPathIndex()
+
+	// Case 1: tx indexed with target pubkey
+	tx1 := &StoreTx{ID: 1}
+	store.addToResolvedPubkeyIndex(1, []string{target})
+	if !store.nodeInResolvedPathViaIndex(tx1, target) {
+		t.Error("should match when index contains target")
 	}
 
-	// Case 2: tx.ResolvedPath contains different node
-	other := "aacafe0000000000"
-	tx2 := &StoreTx{ResolvedPath: []*string{&other}}
-	if nodeInResolvedPath(tx2, target) {
-		t.Error("should not match when ResolvedPath contains different node")
+	// Case 2: tx indexed with different pubkey
+	tx2 := &StoreTx{ID: 2}
+	store.addToResolvedPubkeyIndex(2, []string{"aacafe0000000000"})
+	if store.nodeInResolvedPathViaIndex(tx2, target) {
+		t.Error("should not match when index contains different node")
 	}
 
-	// Case 3: nil ResolvedPath — should match (no data to disambiguate, keep it)
-	tx3 := &StoreTx{}
-	if !nodeInResolvedPath(tx3, target) {
-		t.Error("should match when ResolvedPath is nil (no data to disambiguate)")
-	}
-
-	// Case 4: ResolvedPath with nil elements only — has data but no match
-	tx4 := &StoreTx{ResolvedPath: []*string{nil, nil}}
-	if nodeInResolvedPath(tx4, target) {
-		t.Error("should not match when all ResolvedPath elements are nil")
-	}
-
-	// Case 5: target in observation but not in tx.ResolvedPath
-	tx5 := &StoreTx{
-		ResolvedPath: []*string{&other},
-		Observations: []*StoreObs{
-			{ResolvedPath: []*string{&pk}},
-		},
-	}
-	if !nodeInResolvedPath(tx5, target) {
-		t.Error("should match when observation's ResolvedPath contains target")
+	// Case 3: tx not in index at all — should match (no data to disambiguate)
+	tx3 := &StoreTx{ID: 3}
+	if !store.nodeInResolvedPathViaIndex(tx3, target) {
+		t.Error("should match when tx has no index entries (no data to disambiguate)")
 	}
 }
 
 func TestPathHopIndexIncrementalUpdate(t *testing.T) {
-	// Test that addTxToPathHopIndex and removeTxFromPathHopIndex work correctly
+	// After #800, addTxToPathHopIndex only indexes raw hops (not resolved pubkeys).
+	// Resolved pubkeys are handled by the resolved pubkey membership index.
 	idx := make(map[string][]*StoreTx)
 
-	pk1 := "fullpubkey1"
 	tx1 := &StoreTx{
 		ID:       1,
 		PathJSON: `["ab","cd"]`,
-		ResolvedPath: []*string{&pk1, nil},
 	}
 
 	addTxToPathHopIndex(idx, tx1)
 
-	// Should be indexed under "ab", "cd", and "fullpubkey1"
+	// Should be indexed under "ab" and "cd" only (no resolved pubkey)
 	if len(idx["ab"]) != 1 {
 		t.Errorf("expected 1 entry for 'ab', got %d", len(idx["ab"]))
 	}
 	if len(idx["cd"]) != 1 {
 		t.Errorf("expected 1 entry for 'cd', got %d", len(idx["cd"]))
 	}
-	if len(idx["fullpubkey1"]) != 1 {
-		t.Errorf("expected 1 entry for resolved pubkey, got %d", len(idx["fullpubkey1"]))
-	}
 
 	// Add another tx with overlapping hop
 	tx2 := &StoreTx{
@@ -3766,9 +3754,6 @@ func TestPathHopIndexIncrementalUpdate(t *testing.T) {
 	if _, ok := idx["cd"]; ok {
 		t.Error("expected 'cd' key to be deleted after removal")
 	}
-	if _, ok := idx["fullpubkey1"]; ok {
-		t.Error("expected resolved pubkey key to be deleted after removal")
-	}
 }
 
 func TestMetricsAPIEndpoints(t *testing.T) {
@@ -3808,3 +3793,182 @@ func TestMetricsAPIEndpoints(t *testing.T) {
 		t.Errorf("expected 1 observer in summary, got %v", resp2["observers"])
 	}
 }
+
+// TestNodeHealth_RecentPackets_ResolvedPath verifies that recentPackets in the
+// node health endpoint include resolved_path (regression for Codex review item #2).
+func TestNodeHealth_RecentPackets_ResolvedPath(t *testing.T) {
+	_, router := setupTestServer(t)
+	req := httptest.NewRequest("GET", "/api/nodes/aabbccdd11223344/health", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	var body map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
+		t.Fatalf("json decode: %v", err)
+	}
+	rp, ok := body["recentPackets"].([]interface{})
+	if !ok || len(rp) == 0 {
+		t.Fatal("expected non-empty recentPackets")
+	}
+	// At least one packet should have resolved_path (tx 1 has observations with resolved_path)
+	found := false
+	for _, p := range rp {
+		pm, ok := p.(map[string]interface{})
+		if !ok {
+			continue
+		}
+		if pm["resolved_path"] != nil {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Error("expected at least one recentPacket with resolved_path")
+	}
+}
+
+// TestPacketsExpand_ResolvedPath verifies that expandObservations=true includes
+// resolved_path on expanded observations (regression for Codex review item #3).
+func TestPacketsExpand_ResolvedPath(t *testing.T) {
+	_, router := setupTestServer(t)
+	req := httptest.NewRequest("GET", "/api/packets?expand=observations&limit=10", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	var body map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
+		t.Fatalf("json decode: %v", err)
+	}
+	packets, ok := body["packets"].([]interface{})
+	if !ok || len(packets) == 0 {
+		t.Fatal("expected non-empty packets")
+	}
+	// Find a packet with observations that should have resolved_path
+	found := false
+	for _, p := range packets {
+		pm, ok := p.(map[string]interface{})
+		if !ok {
+			continue
+		}
+		obs, ok := pm["observations"].([]interface{})
+		if !ok {
+			continue
+		}
+		for _, o := range obs {
+			om, ok := o.(map[string]interface{})
+			if !ok {
+				continue
+			}
+			if om["resolved_path"] != nil {
+				found = true
+				break
+			}
+		}
+		if found {
+			break
+		}
+	}
+	if !found {
+		t.Error("expected at least one expanded observation with resolved_path")
+	}
+}
+
+// TestPacketDetailFallsBackToDBWhenStoreMisses verifies that handlePacketDetail
+// serves transmissions present in the DB but absent from the in-memory store.
+// This is the recentAdverts → "Not found" bug (#827).
+func TestPacketDetailFallsBackToDBWhenStoreMisses(t *testing.T) {
+	srv, router := setupTestServer(t)
+	// Insert a transmission directly into the DB AFTER store.Load(), so the
+	// in-memory PacketStore won't see it. Mirrors the production case where
+	// the store has pruned an entry but the DB still has it.
+	const dbOnlyHash = "deadbeef00112233"
+	now := time.Now().UTC().Format(time.RFC3339)
+	if _, err := srv.db.conn.Exec(`INSERT INTO transmissions
+		(raw_hex, hash, first_seen, route_type, payload_type, decoded_json)
+		VALUES ('FFEE', ?, ?, 1, 4, '{"type":"ADVERT"}')`, dbOnlyHash, now); err != nil {
+		t.Fatalf("insert: %v", err)
+	}
+	var txID int
+	if err := srv.db.conn.QueryRow("SELECT id FROM transmissions WHERE hash = ?", dbOnlyHash).Scan(&txID); err != nil {
+		t.Fatalf("lookup tx id: %v", err)
+	}
+	if _, err := srv.db.conn.Exec(`INSERT INTO observations
+		(transmission_id, observer_idx, snr, rssi, path_json, timestamp)
+		VALUES (?, 1, 7.5, -99, '[]', ?)`, txID, time.Now().Unix()); err != nil {
+		t.Fatalf("insert obs: %v", err)
+	}
+
+	// Confirm the store really doesn't have it (precondition for the fix).
+	if got := srv.store.GetPacketByHash(dbOnlyHash); got != nil {
+		t.Fatalf("test precondition failed: store unexpectedly has %s", dbOnlyHash)
+	}
+
+	req := httptest.NewRequest("GET", "/api/packets/"+dbOnlyHash, nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d (body: %s)", w.Code, w.Body.String())
+	}
+	var body map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
+		t.Fatal(err)
+	}
+	pkt, ok := body["packet"].(map[string]interface{})
+	if !ok {
+		t.Fatal("expected packet object")
+	}
+	if pkt["hash"] != dbOnlyHash {
+		t.Errorf("expected hash %s, got %v", dbOnlyHash, pkt["hash"])
+	}
+	// Observations fallback should populate from DB too.
+	obs, _ := body["observations"].([]interface{})
+	if len(obs) == 0 {
+		t.Errorf("expected DB observations to be returned, got 0")
+	}
+}
+
+// TestPacketDetail404WhenAbsentFromBoth verifies that a hash present in
+// neither store nor DB still returns 404 (no false positives from the fallback).
+func TestPacketDetail404WhenAbsentFromBoth(t *testing.T) {
+	_, router := setupTestServer(t)
+	req := httptest.NewRequest("GET", "/api/packets/0011223344556677", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+	if w.Code != 404 {
+		t.Errorf("expected 404, got %d (body: %s)", w.Code, w.Body.String())
+	}
+}
+
+// TestPacketDetailPrefersStoreOverDB verifies the store result wins when the
+// hash exists in both — the DB fallback must not double-fetch / overwrite.
+func TestPacketDetailPrefersStoreOverDB(t *testing.T) {
+	srv, router := setupTestServer(t)
+	// abc123def4567890 is seeded in both DB and (after Load) the store.
+	const hash = "abc123def4567890"
+	if got := srv.store.GetPacketByHash(hash); got == nil {
+		t.Fatalf("test precondition failed: store should have %s", hash)
+	}
+
+	req := httptest.NewRequest("GET", "/api/packets/"+hash, nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	var body map[string]interface{}
+	json.Unmarshal(w.Body.Bytes(), &body)
+	pkt, _ := body["packet"].(map[string]interface{})
+	if pkt == nil || pkt["hash"] != hash {
+		t.Fatalf("expected packet with hash %s, got %v", hash, pkt)
+	}
+	// observation_count comes from store observations (2 seeded for tx 1).
+	if cnt, _ := body["observation_count"].(float64); cnt != 2 {
+		t.Errorf("expected observation_count=2 (from store), got %v", body["observation_count"])
+	}
+}

cmd/server/stats_memory_test.go

@@ -0,0 +1,95 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+// TestStatsMemoryFields verifies that /api/stats exposes the new memory
+// breakdown introduced for issue #832: storeDataMB, processRSSMB,
+// goHeapInuseMB, goSysMB, plus the deprecated trackedMB alias.
+//
+// We assert presence, type, sign, and ordering invariants — but NOT
+// "RSS within X% of true RSS" because that is flaky in CI under cgo,
+// containerization, and shared-runner load.
+func TestStatsMemoryFields(t *testing.T) {
+	_, router := setupTestServer(t)
+	req := httptest.NewRequest("GET", "/api/stats", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	if w.Code != 200 {
+		t.Fatalf("expected 200, got %d", w.Code)
+	}
+	var body map[string]interface{}
+	if err := json.Unmarshal(w.Body.Bytes(), &body); err != nil {
+		t.Fatalf("json decode: %v", err)
+	}
+
+	required := []string{"trackedMB", "storeDataMB", "processRSSMB", "goHeapInuseMB", "goSysMB"}
+	values := make(map[string]float64, len(required))
+	for _, k := range required {
+		v, ok := body[k]
+		if !ok {
+			t.Fatalf("missing field %q in /api/stats response", k)
+		}
+		f, ok := v.(float64)
+		if !ok {
+			t.Fatalf("field %q is %T, expected float64", k, v)
+		}
+		if f < 0 {
+			t.Errorf("field %q is negative: %v", k, f)
+		}
+		values[k] = f
+	}
+
+	// trackedMB is a deprecated alias for storeDataMB; they must match.
+	if values["trackedMB"] != values["storeDataMB"] {
+		t.Errorf("trackedMB (%v) != storeDataMB (%v); they must remain aliased",
+			values["trackedMB"], values["storeDataMB"])
+	}
+
+	// Ordering invariants. goSys is the runtime's view of total OS memory;
+	// HeapInuse is a subset of it. storeData is a subset of HeapInuse.
+	// processRSS may be 0 in environments without /proc — treat 0 as
+	// "unknown" rather than a failure.
+	if values["goHeapInuseMB"] > values["goSysMB"]+0.5 {
+		t.Errorf("invariant violated: goHeapInuseMB (%v) > goSysMB (%v)",
+			values["goHeapInuseMB"], values["goSysMB"])
+	}
+	if values["storeDataMB"] > values["goHeapInuseMB"]+0.5 && values["storeDataMB"] > 0 {
+		// In the test fixture storeDataMB is typically 0 (no packets in
+		// store); only enforce the bound when both are nonzero.
+		t.Errorf("invariant violated: storeDataMB (%v) > goHeapInuseMB (%v)",
+			values["storeDataMB"], values["goHeapInuseMB"])
+	}
+	if values["processRSSMB"] > 0 && values["goSysMB"] > 0 {
+		// goSys can briefly exceed RSS if pages are reserved-but-not-touched,
+		// so allow some slack.
+		if values["goSysMB"] > values["processRSSMB"]*4 {
+			t.Errorf("suspicious: goSysMB (%v) >> processRSSMB (%v)",
+				values["goSysMB"], values["processRSSMB"])
+		}
+	}
+}
+
+// TestStatsMemoryFieldsRawJSON spot-checks that the JSON wire format uses
+// the documented camelCase names (no accidental rename through struct tags).
+func TestStatsMemoryFieldsRawJSON(t *testing.T) {
+	_, router := setupTestServer(t)
+	req := httptest.NewRequest("GET", "/api/stats", nil)
+	w := httptest.NewRecorder()
+	router.ServeHTTP(w, req)
+
+	body := w.Body.String()
+	for _, key := range []string{
+		`"trackedMB":`, `"storeDataMB":`,
+		`"processRSSMB":`, `"goHeapInuseMB":`, `"goSysMB":`,
+	} {
+		if !strings.Contains(body, key) {
+			t.Errorf("missing %s in raw response: %s", key, body)
+		}
+	}
+}

cmd/server/store_tophops_test.go

@@ -0,0 +1,116 @@
+package main
+
+import (
+	"testing"
+)
+
+func f64(v float64) *float64 { return &v }
+
+func TestDedupeTopHopsByPair(t *testing.T) {
+	hops := []distHopRecord{
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 100, Type: "R↔R", SNR: f64(5.0), Hash: "h1", Timestamp: "t1"},
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 90, Type: "R↔R", SNR: f64(8.0), Hash: "h2", Timestamp: "t2"},
+		{FromPk: "BBB", ToPk: "AAA", FromName: "B", ToName: "A", Dist: 80, Type: "R↔R", SNR: f64(3.0), Hash: "h3", Timestamp: "t3"},
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 70, Type: "R↔R", SNR: f64(6.0), Hash: "h4", Timestamp: "t4"},
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 60, Type: "R↔R", SNR: f64(4.0), Hash: "h5", Timestamp: "t5"},
+		{FromPk: "CCC", ToPk: "DDD", FromName: "C", ToName: "D", Dist: 50, Type: "C↔R", SNR: f64(7.0), Hash: "h6", Timestamp: "t6"},
+	}
+
+	result := dedupeHopsByPair(hops, 20)
+
+	if len(result) != 2 {
+		t.Fatalf("expected 2 entries, got %d", len(result))
+	}
+
+	// First entry: A↔B pair, max distance = 100, obsCount = 5
+	ab := result[0]
+	if ab["dist"].(float64) != 100 {
+		t.Errorf("expected dist 100, got %v", ab["dist"])
+	}
+	if ab["obsCount"].(int) != 5 {
+		t.Errorf("expected obsCount 5, got %v", ab["obsCount"])
+	}
+	if ab["hash"].(string) != "h1" {
+		t.Errorf("expected hash h1 (from max-dist record), got %v", ab["hash"])
+	}
+	if ab["bestSnr"].(float64) != 8.0 {
+		t.Errorf("expected bestSnr 8.0, got %v", ab["bestSnr"])
+	}
+	// medianSnr of [3,4,5,6,8] = 5.0
+	if ab["medianSnr"].(float64) != 5.0 {
+		t.Errorf("expected medianSnr 5.0, got %v", ab["medianSnr"])
+	}
+
+	// Second entry: C↔D pair
+	cd := result[1]
+	if cd["dist"].(float64) != 50 {
+		t.Errorf("expected dist 50, got %v", cd["dist"])
+	}
+	if cd["obsCount"].(int) != 1 {
+		t.Errorf("expected obsCount 1, got %v", cd["obsCount"])
+	}
+}
+
+func TestDedupeTopHopsReversePairMerges(t *testing.T) {
+	hops := []distHopRecord{
+		{FromPk: "BBB", ToPk: "AAA", FromName: "B", ToName: "A", Dist: 50, Type: "R↔R", Hash: "h1"},
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 80, Type: "R↔R", Hash: "h2"},
+	}
+	result := dedupeHopsByPair(hops, 20)
+	if len(result) != 1 {
+		t.Fatalf("expected 1 entry, got %d", len(result))
+	}
+	if result[0]["obsCount"].(int) != 2 {
+		t.Errorf("expected obsCount 2, got %v", result[0]["obsCount"])
+	}
+	if result[0]["dist"].(float64) != 80 {
+		t.Errorf("expected dist 80, got %v", result[0]["dist"])
+	}
+}
+
+func TestDedupeTopHopsNilSNR(t *testing.T) {
+	hops := []distHopRecord{
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 100, Type: "R↔R", SNR: nil, Hash: "h1"},
+		{FromPk: "AAA", ToPk: "BBB", FromName: "A", ToName: "B", Dist: 90, Type: "R↔R", SNR: nil, Hash: "h2"},
+	}
+	result := dedupeHopsByPair(hops, 20)
+	if len(result) != 1 {
+		t.Fatalf("expected 1 entry, got %d", len(result))
+	}
+	if result[0]["bestSnr"] != nil {
+		t.Errorf("expected bestSnr nil, got %v", result[0]["bestSnr"])
+	}
+	if result[0]["medianSnr"] != nil {
+		t.Errorf("expected medianSnr nil, got %v", result[0]["medianSnr"])
+	}
+}
+
+func TestDedupeTopHopsLimit(t *testing.T) {
+	// Generate 25 unique pairs, verify limit=20 caps output
+	hops := make([]distHopRecord, 25)
+	for i := range hops {
+		hops[i] = distHopRecord{
+			FromPk: "A", ToPk: string(rune('a' + i)),
+			Dist: float64(i), Type: "R↔R", Hash: "h",
+		}
+	}
+	result := dedupeHopsByPair(hops, 20)
+	if len(result) != 20 {
+		t.Errorf("expected 20 entries, got %d", len(result))
+	}
+}
+
+func TestDedupeTopHopsEvenMedian(t *testing.T) {
+	// Even count: median = avg of two middle values
+	hops := []distHopRecord{
+		{FromPk: "A", ToPk: "B", Dist: 10, Type: "R↔R", SNR: f64(2.0), Hash: "h1"},
+		{FromPk: "A", ToPk: "B", Dist: 20, Type: "R↔R", SNR: f64(4.0), Hash: "h2"},
+		{FromPk: "A", ToPk: "B", Dist: 30, Type: "R↔R", SNR: f64(6.0), Hash: "h3"},
+		{FromPk: "A", ToPk: "B", Dist: 40, Type: "R↔R", SNR: f64(8.0), Hash: "h4"},
+	}
+	result := dedupeHopsByPair(hops, 20)
+	// sorted SNR: [2,4,6,8], median = (4+6)/2 = 5.0
+	if result[0]["medianSnr"].(float64) != 5.0 {
+		t.Errorf("expected medianSnr 5.0, got %v", result[0]["medianSnr"])
+	}
+}

cmd/server/testdata/golden/shapes.json

@@ -42,14 +42,20 @@
             "type": {
               "type": "string"
             },
-            "snr": {
-              "type": "number"
-            },
             "hash": {
               "type": "string"
             },
             "timestamp": {
               "type": "string"
+            },
+            "bestSnr": {
+              "type": "number"
+            },
+            "medianSnr": {
+              "type": "number"
+            },
+            "obsCount": {
+              "type": "number"
             }
           }
         }
@@ -1580,4 +1586,4 @@
       }
     }
   }
-}
+}

cmd/server/touch_last_seen_test.go

@@ -69,13 +69,11 @@ func TestTouchRelayLastSeen_Debouncing(t *testing.T) {
 		lastSeenTouched: make(map[string]time.Time),
 	}
 
-	pk := "relay1"
-	tx := &StoreTx{
-		ResolvedPath: []*string{&pk},
-	}
+	// After #800, touchRelayLastSeen takes a []string of pubkeys (from decode-window)
+	pks := []string{"relay1"}
 
 	now := time.Now()
-	s.touchRelayLastSeen(tx, now)
+	s.touchRelayLastSeen(pks, now)
 
 	// Verify it was written
 	var lastSeen sql.NullString
@@ -88,7 +86,7 @@ func TestTouchRelayLastSeen_Debouncing(t *testing.T) {
 	db.conn.Exec("UPDATE nodes SET last_seen = NULL WHERE public_key = ?", "relay1")
 
 	// Call again within 5 minutes — should be debounced (no write)
-	s.touchRelayLastSeen(tx, now.Add(2*time.Minute))
+	s.touchRelayLastSeen(pks, now.Add(2*time.Minute))
 
 	db.conn.QueryRow("SELECT last_seen FROM nodes WHERE public_key = ?", "relay1").Scan(&lastSeen)
 	if lastSeen.Valid {
@@ -96,14 +94,14 @@ func TestTouchRelayLastSeen_Debouncing(t *testing.T) {
 	}
 
 	// Call after 5 minutes — should write again
-	s.touchRelayLastSeen(tx, now.Add(6*time.Minute))
+	s.touchRelayLastSeen(pks, now.Add(6*time.Minute))
 	db.conn.QueryRow("SELECT last_seen FROM nodes WHERE public_key = ?", "relay1").Scan(&lastSeen)
 	if !lastSeen.Valid {
 		t.Fatal("expected write after debounce interval expired")
 	}
 }
 
-func TestTouchRelayLastSeen_SkipsNilResolvedPath(t *testing.T) {
+func TestTouchRelayLastSeen_SkipsEmptyPubkeys(t *testing.T) {
 	db := setupTestDB(t)
 	defer db.Close()
 
@@ -112,13 +110,9 @@ func TestTouchRelayLastSeen_SkipsNilResolvedPath(t *testing.T) {
 		lastSeenTouched: make(map[string]time.Time),
 	}
 
-	// tx with nil entries and empty resolved_path
-	tx := &StoreTx{
-		ResolvedPath: []*string{nil, nil},
-	}
-
-	// Should not panic or error
-	s.touchRelayLastSeen(tx, time.Now())
+	// Empty pubkeys — should not panic or error
+	s.touchRelayLastSeen([]string{}, time.Now())
+	s.touchRelayLastSeen(nil, time.Now())
 }
 
 func TestTouchRelayLastSeen_NilDB(t *testing.T) {
@@ -127,11 +121,6 @@ func TestTouchRelayLastSeen_NilDB(t *testing.T) {
 		lastSeenTouched: make(map[string]time.Time),
 	}
 
-	pk := "abc"
-	tx := &StoreTx{
-		ResolvedPath: []*string{&pk},
-	}
-
 	// Should not panic with nil db
-	s.touchRelayLastSeen(tx, time.Now())
+	s.touchRelayLastSeen([]string{"abc"}, time.Now())
 }

cmd/server/tracked_bytes_test.go

@@ -0,0 +1,166 @@
+package main
+
+import (
+	"testing"
+	"time"
+)
+
+// TestEstimateStoreTxBytes_ReasonableValues verifies the estimate function
+// returns reasonable values for different packet sizes.
+func TestEstimateStoreTxBytes_ReasonableValues(t *testing.T) {
+	tx := &StoreTx{
+		Hash:        "abcdef1234567890",
+		RawHex:      "deadbeef",
+		DecodedJSON: `{"type":"GRP_TXT"}`,
+		PathJSON:    `["hop1","hop2","hop3"]`,
+		parsedPath:  []string{"hop1", "hop2", "hop3"},
+		pathParsed:  true,
+	}
+	got := estimateStoreTxBytes(tx)
+
+	// Should be at least base (384) + maps (200) + indexes + path/subpath costs
+	if got < 700 {
+		t.Errorf("estimate too low for 3-hop tx: %d", got)
+	}
+	if got > 5000 {
+		t.Errorf("estimate unreasonably high for 3-hop tx: %d", got)
+	}
+}
+
+// TestEstimateStoreTxBytes_ManyHopsSubpaths verifies that packets with many
+// hops estimate significantly more due to O(path²) subpath index entries.
+func TestEstimateStoreTxBytes_ManyHopsSubpaths(t *testing.T) {
+	tx2 := &StoreTx{
+		Hash:       "aabb",
+		parsedPath: []string{"a", "b"},
+		pathParsed: true,
+	}
+	tx10 := &StoreTx{
+		Hash:       "aabb",
+		parsedPath: []string{"a", "b", "c", "d", "e", "f", "g", "h", "i", "j"},
+		pathParsed: true,
+	}
+	est2 := estimateStoreTxBytes(tx2)
+	est10 := estimateStoreTxBytes(tx10)
+
+	// 10 hops → 45 subpath combos × 40 = 1800 bytes just for subpaths
+	if est10 <= est2 {
+		t.Errorf("10-hop (%d) should estimate more than 2-hop (%d)", est10, est2)
+	}
+	if est10 < est2+1500 {
+		t.Errorf("10-hop (%d) should estimate at least 1500 more than 2-hop (%d)", est10, est2)
+	}
+}
+
+// TestEstimateStoreObsBytes_AfterRefactor verifies that after #800 refactor,
+// observations no longer have ResolvedPath overhead in their estimate.
+func TestEstimateStoreObsBytes_AfterRefactor(t *testing.T) {
+	obs := &StoreObs{
+		ObserverID: "obs1",
+		PathJSON:   `["a","b"]`,
+	}
+
+	est := estimateStoreObsBytes(obs)
+	if est <= 0 {
+		t.Errorf("estimate should be positive, got %d", est)
+	}
+	// After #800, all obs estimates should be the same (no RP field variation)
+	obs2 := &StoreObs{
+		ObserverID: "obs1",
+		PathJSON:   `["a","b"]`,
+	}
+	est2 := estimateStoreObsBytes(obs2)
+	if est != est2 {
+		t.Errorf("estimates should be equal after #800 (no RP field), got %d vs %d", est, est2)
+	}
+}
+
+// TestEstimateStoreObsBytes_ManyObservations verifies that 15 observations
+// estimate significantly more than 1.
+func TestEstimateStoreObsBytes_ManyObservations(t *testing.T) {
+	est1 := estimateStoreObsBytes(&StoreObs{ObserverID: "a", PathJSON: `["x"]`})
+	est15 := int64(0)
+	for i := 0; i < 15; i++ {
+		est15 += estimateStoreObsBytes(&StoreObs{ObserverID: "a", PathJSON: `["x"]`})
+	}
+	if est15 <= est1*10 {
+		t.Errorf("15 obs total (%d) should be >10x single obs (%d)", est15, est1)
+	}
+}
+
+// TestTrackedBytesMatchesSumAfterInsert verifies that trackedBytes equals the
+// sum of individual estimates after inserting packets via makeTestStore.
+func TestTrackedBytesMatchesSumAfterInsert(t *testing.T) {
+	store := makeTestStore(20, time.Now().Add(-2*time.Hour), 5)
+
+	// Manually compute trackedBytes as sum of estimates
+	var expectedSum int64
+	for _, tx := range store.packets {
+		expectedSum += estimateStoreTxBytes(tx)
+		for _, obs := range tx.Observations {
+			expectedSum += estimateStoreObsBytes(obs)
+		}
+	}
+
+	if store.trackedBytes != expectedSum {
+		t.Errorf("trackedBytes=%d, expected sum=%d", store.trackedBytes, expectedSum)
+	}
+}
+
+// TestEvictionTriggersWithImprovedEstimates verifies that eviction triggers
+// at the right point with the improved (higher) estimates.
+func TestEvictionTriggersWithImprovedEstimates(t *testing.T) {
+	store := makeTestStore(100, time.Now().Add(-10*time.Hour), 5)
+
+	// trackedBytes for 100 packets is small — artificially set maxMemoryMB
+	// so highWatermark is just below trackedBytes to trigger eviction.
+	highWatermarkBytes := store.trackedBytes - 1000
+	if highWatermarkBytes < 1 {
+		highWatermarkBytes = 1
+	}
+	// maxMemoryMB * 1048576 = highWatermark, so maxMemoryMB = ceil(highWatermarkBytes / 1048576)
+	// But that'll be 0 for small values. Instead, directly set trackedBytes high.
+	store.trackedBytes = 6 * 1048576 // 6MB
+	store.maxMemoryMB = 3            // 3MB limit
+
+	beforeCount := len(store.packets)
+	store.RunEviction()
+	afterCount := len(store.packets)
+
+	if afterCount >= beforeCount {
+		t.Errorf("expected eviction to remove packets: before=%d, after=%d, trackedBytes=%d, maxMB=%d",
+			beforeCount, afterCount, store.trackedBytes, store.maxMemoryMB)
+	}
+	// trackedBytes should have decreased
+	if store.trackedBytes >= 6*1048576 {
+		t.Errorf("trackedBytes should have decreased after eviction")
+	}
+}
+
+// BenchmarkEstimateStoreTxBytes verifies the estimate function is fast.
+func BenchmarkEstimateStoreTxBytes(b *testing.B) {
+	tx := &StoreTx{
+		Hash:        "abcdef1234567890",
+		RawHex:      "deadbeefdeadbeef",
+		DecodedJSON: `{"type":"GRP_TXT","payload":"hello"}`,
+		PathJSON:    `["hop1","hop2","hop3","hop4","hop5"]`,
+		parsedPath:  []string{"hop1", "hop2", "hop3", "hop4", "hop5"},
+		pathParsed:  true,
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		estimateStoreTxBytes(tx)
+	}
+}
+
+// BenchmarkEstimateStoreObsBytes verifies the obs estimate function is fast.
+func BenchmarkEstimateStoreObsBytes(b *testing.B) {
+	obs := &StoreObs{
+		ObserverID: "observer1234",
+		PathJSON:   `["a","b","c"]`,
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		estimateStoreObsBytes(obs)
+	}
+}

cmd/server/types.go

@@ -68,8 +68,26 @@ type StatsResponse struct {
 	Commit             string     `json:"commit"`
 	BuildTime          string     `json:"buildTime"`
 	Counts             RoleCounts `json:"counts"`
-	Backfilling        bool       `json:"backfilling"`
-	BackfillProgress   float64    `json:"backfillProgress"`
+	Backfilling            bool       `json:"backfilling"`
+	BackfillProgress       float64    `json:"backfillProgress"`
+	SignatureDrops         int64      `json:"signatureDrops,omitempty"`
+	HashMigrationComplete  bool       `json:"hashMigrationComplete"`
+
+	// Memory accounting (issue #832). All values in MB.
+	//
+	// StoreDataMB ("trackedMB" historically) is the in-store packet byte
+	// estimate — useful packet bytes only. Subset of HeapInuse. Used as
+	// the eviction watermark input. NOT a proxy for RSS; ops dashboards
+	// should prefer ProcessRSSMB for capacity decisions.
+	//
+	// Old field name TrackedMB is retained for backward compatibility
+	// with pre-v3.6 consumers; it carries the same value as StoreDataMB
+	// and is deprecated.
+	TrackedMB     float64 `json:"trackedMB"`     // deprecated alias for storeDataMB
+	StoreDataMB   float64 `json:"storeDataMB"`   // in-store packet bytes (subset of heap)
+	ProcessRSSMB  float64 `json:"processRSSMB"`  // process RSS from /proc (Linux) or runtime.Sys fallback
+	GoHeapInuseMB float64 `json:"goHeapInuseMB"` // runtime.MemStats.HeapInuse
+	GoSysMB       float64 `json:"goSysMB"`       // runtime.MemStats.Sys (total Go-managed)
 }
 
 // ─── Health ────────────────────────────────────────────────────────────────────
@@ -176,6 +194,7 @@ type PerfPacketStoreStats struct {
 	MaxPackets        int                `json:"maxPackets"`
 	EstimatedMB       float64            `json:"estimatedMB"`
 	TrackedMB         float64            `json:"trackedMB"`
+	AvgBytesPerPacket int64              `json:"avgBytesPerPacket"`
 	MaxMB             int                `json:"maxMB"`
 	Indexes           PacketStoreIndexes `json:"indexes"`
 }
@@ -244,7 +263,6 @@ type TransmissionResp struct {
 	SNR              interface{}      `json:"snr"`
 	RSSI             interface{}      `json:"rssi"`
 	PathJSON         interface{}      `json:"path_json"`
-	ResolvedPath     []*string        `json:"resolved_path,omitempty"`
 	Direction        interface{}      `json:"direction"`
 	Score            interface{}      `json:"score,omitempty"`
 	Observations     []ObservationResp `json:"observations,omitempty"`
@@ -259,7 +277,9 @@ type ObservationResp struct {
 	SNR            interface{} `json:"snr"`
 	RSSI           interface{} `json:"rssi"`
 	PathJSON       interface{} `json:"path_json"`
-	ResolvedPath   []*string   `json:"resolved_path,omitempty"`
+	ResolvedPath   interface{} `json:"resolved_path,omitempty"`
+	Direction      interface{} `json:"direction,omitempty"`
+	RawHex         interface{} `json:"raw_hex,omitempty"`
 	Timestamp      interface{} `json:"timestamp"`
 }
 
@@ -468,6 +488,7 @@ type NodeAnalyticsResponse struct {
 	PeerInteractions    []PeerInteraction       `json:"peerInteractions"`
 	UptimeHeatmap       []HeatmapCell           `json:"uptimeHeatmap"`
 	ComputedStats       ComputedNodeStats       `json:"computedStats"`
+	ClockSkew           *NodeClockSkew          `json:"clockSkew,omitempty"`
 }
 
 // ─── Analytics — RF ────────────────────────────────────────────────────────────
@@ -660,7 +681,9 @@ type DistanceHop struct {
 	ToPk      string      `json:"toPk"`
 	Dist      float64     `json:"dist"`
 	Type      string      `json:"type"`
-	SNR       interface{} `json:"snr"`
+	BestSnr   interface{} `json:"bestSnr"`
+	MedianSnr interface{} `json:"medianSnr"`
+	ObsCount  int         `json:"obsCount"`
 	Hash      string      `json:"hash"`
 	Timestamp string      `json:"timestamp"`
 }

config.example.json

@@ -1,10 +1,13 @@
 {
   "port": 3000,
   "apiKey": "your-secret-api-key-here",
+  "nodeBlacklist": [],
+  "_comment_nodeBlacklist": "Public keys of nodes to hide from all API responses. Use for trolls, offensive names, or nodes reporting false data that operators refuse to fix.",
   "retention": {
     "nodeDays": 7,
+    "observerDays": 14,
     "packetDays": 30,
-    "_comment": "nodeDays: nodes not seen in N days are moved to inactive_nodes (default 7). packetDays: transmissions+observations older than N days are deleted daily (0 = disabled)."
+    "_comment": "nodeDays: nodes not seen in N days moved to inactive_nodes (default 7). observerDays: observers not sending data in N days are removed (-1 = keep forever, default 14). packetDays: transmissions older than N days are deleted (0 = disabled)."
   },
   "https": {
     "cert": "/path/to/cert.pem",
@@ -125,7 +128,7 @@
     }
   ],
   "channelKeys": {
-    "public": "8b3387e9c5cdea6ac9e5edbaa115cd72"
+    "Public": "8b3387e9c5cdea6ac9e5edbaa115cd72"
   },
   "hashChannels": [
     "#LongFast",
@@ -153,6 +156,16 @@
     ],
     "zoom": 9
   },
+  "geo_filter": {
+    "polygon": [
+      [37.80, -122.52],
+      [37.80, -121.80],
+      [37.20, -121.80],
+      [37.20, -122.52]
+    ],
+    "bufferKm": 20,
+    "_comment": "Optional. Restricts ingestion and API responses to nodes within the polygon + bufferKm. Polygon is an array of [lat, lon] pairs (minimum 3). Use tools/geofilter-builder.html to draw a polygon visually. Remove this section to disable filtering. Nodes with no GPS fix are always allowed through."
+  },
   "regions": {
     "SJC": "San Jose, US",
     "SFO": "San Francisco, US",

docs/user-guide/configuration.md

@@ -176,6 +176,19 @@ Lower values = fresher data but more server load.
 
 Provide cert and key paths to enable HTTPS.
 
+## Geographic filtering
+
+```json
+"geo_filter": {
+  "polygon": [[51.55, 3.80], [51.55, 5.90], [50.65, 5.90], [50.65, 3.80]],
+  "bufferKm": 20
+}
+```
+
+Restricts ingestion and API responses to nodes within the polygon plus a buffer margin. Remove the block to disable filtering. Nodes with no GPS fix always pass through.
+
+See [Geographic Filtering](geofilter.md) for the full guide including the visual polygon builder and the prune script for cleaning up historical data.
+
 ## Home page
 
 The `home` section customizes the onboarding experience. See `config.example.json` for the full structure including `steps`, `checklist`, and `footerLinks`.

docs/user-guide/customization.md

@@ -66,6 +66,12 @@ Click **Import JSON** and paste a previously exported theme. The customizer load
 
 Click **Reset to Defaults** to restore all settings to the built-in defaults.
 
+## GeoFilter Builder
+
+The Export tab includes a **GeoFilter Builder →** link. Click it to open a Leaflet map where you can draw a polygon boundary for your deployment area. The tool generates a `geo_filter` block you can paste directly into `config.json`.
+
+See [Geographic Filtering](geofilter.md) for full details on what geo filtering does and how to configure it.
+
 ## How it works
 
 The customizer writes CSS custom properties (variables) to override the defaults. Exported JSON maps directly to the `theme`, `nodeColors`, `branding`, and `home` sections of [config.json](configuration.md).

docs/user-guide/geofilter.md

@@ -0,0 +1,114 @@
+# Geographic Filtering
+
+CoreScope supports geographic filtering to restrict which nodes are ingested and returned in API responses. This is useful for public-facing deployments that should only show activity in a specific region.
+
+## How it works
+
+Geographic filtering operates at two levels:
+
+- **Ingest time** — ADVERT packets carrying GPS coordinates are rejected by the ingestor if the node falls outside the configured area. The node never reaches the database.
+- **API responses** — Nodes already in the database are filtered from the `/api/nodes` response if they fall outside the area. This covers nodes ingested before the filter was configured.
+
+Nodes with no GPS fix (`lat=0, lon=0` or missing coordinates) always pass the filter regardless of configuration.
+
+## Configuration
+
+Add a `geo_filter` block to `config.json`:
+
+```json
+"geo_filter": {
+  "polygon": [
+    [51.55, 3.80],
+    [51.55, 5.90],
+    [50.65, 5.90],
+    [50.65, 3.80]
+  ],
+  "bufferKm": 20
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `polygon` | `[[lat, lon], ...]` | Array of at least 3 coordinate pairs defining the boundary |
+| `bufferKm` | number | Extra distance (km) around the polygon edge that is also accepted. `0` = exact boundary |
+
+Both the server and the ingestor read `geo_filter` from `config.json`. Restart both after changing this section.
+
+To disable filtering entirely, remove the `geo_filter` block.
+
+### Legacy bounding box
+
+An older bounding box format is also supported as a fallback when no `polygon` is present:
+
+```json
+"geo_filter": {
+  "latMin": 50.65,
+  "latMax": 51.55,
+  "lonMin": 3.80,
+  "lonMax": 5.90
+}
+```
+
+Prefer the polygon format — it supports irregular shapes and the `bufferKm` margin.
+
+## API endpoint
+
+The current geo filter configuration is exposed at:
+
+```
+GET /api/config/geo-filter
+```
+
+The frontend reads this endpoint to display the active filter. No authentication is required (the endpoint returns config, not private data).
+
+## GeoFilter Builder
+
+The simplest way to create a polygon is the included visual builder:
+
+**File:** `tools/geofilter-builder.html`
+
+Open it directly in a browser — it runs entirely client-side, no server required:
+
+```bash
+# From the project root
+open tools/geofilter-builder.html          # macOS
+xdg-open tools/geofilter-builder.html     # Linux
+start tools/geofilter-builder.html        # Windows
+```
+
+**Workflow:**
+
+1. The map opens centered on Belgium by default. Navigate to your region.
+2. Click on the map to add polygon vertices. Each click adds a numbered point.
+3. Add at least 3 points to form a closed polygon.
+4. Adjust **Buffer km** (default 20) to add a margin around the polygon edge.
+5. The generated JSON block appears at the bottom of the page — copy it directly into `config.json`.
+6. Use **↩ Undo** to remove the last point, **✕ Clear** to start over.
+
+The output is a complete `{ "geo_filter": { ... } }` block ready to paste into `config.json`.
+
+## Cleaning up historical nodes
+
+The ingestor prevents new out-of-bounds nodes from being ingested, but it does not retroactively remove nodes that were stored before the filter was configured. For that, use the prune script.
+
+**File:** `scripts/prune-nodes-outside-geo-filter.py`
+
+```bash
+# Dry run — shows what would be deleted without making any changes
+python3 scripts/prune-nodes-outside-geo-filter.py --dry-run
+
+# Default paths: /app/data/meshcore.db and /app/config.json
+python3 scripts/prune-nodes-outside-geo-filter.py
+
+# Custom paths
+python3 scripts/prune-nodes-outside-geo-filter.py /path/to/meshcore.db \
+  --config /path/to/config.json
+
+# In Docker — run inside the container
+docker exec -it meshcore-analyzer \
+  python3 /app/scripts/prune-nodes-outside-geo-filter.py --dry-run
+```
+
+The script reads `geo_filter.polygon` and `geo_filter.bufferKm` from config, lists the nodes that fall outside, then asks for `yes` confirmation before deleting. Nodes without coordinates are always kept.
+
+This is a **one-time migration tool** — run it once after first configuring `geo_filter` to clean up pre-filter data. The ingestor handles all subsequent filtering automatically at ingest time.

public/analytics.js

@@ -28,7 +28,7 @@
 
   function barChart(data, labels, colors, w = 800, h = 220, pad = 40) {
     const max = Math.max(...data, 1);
-    const barW = Math.min((w - pad * 2) / data.length - 2, 30);
+    const barW = Math.max(1, Math.min((w - pad * 2) / data.length - 2, 30));
     let svg = `<svg viewBox="0 0 ${w} ${h}" style="width:100%;max-height:${h}px" role="img" aria-label="Bar chart showing data distribution"><title>Bar chart showing data distribution</title>`;
     // Grid
     for (let i = 0; i <= 4; i++) {
@@ -87,6 +87,7 @@
             <button class="tab-btn" data-tab="distance">Distance</button>
             <button class="tab-btn" data-tab="neighbor-graph">Neighbor Graph</button>
             <button class="tab-btn" data-tab="rf-health">RF Health</button>
+            <button class="tab-btn" data-tab="clock-health">Clock Health</button>
             <button class="tab-btn" data-tab="prefix-tool">Prefix Tool</button>
           </div>
         </div>
@@ -181,6 +182,7 @@
       case 'distance': await renderDistanceTab(el); break;
       case 'neighbor-graph': await renderNeighborGraphTab(el); break;
       case 'rf-health': await renderRFHealthTab(el); break;
+      case 'clock-health': await renderClockHealthTab(el); break;
       case 'prefix-tool': await renderPrefixTool(el); break;
     }
     // Auto-apply column resizing to all analytics tables
@@ -261,7 +263,25 @@
       <div class="analytics-row">
         <div class="analytics-card flex-1">
           <h3>📈 Packets / Hour</h3>
-          ${barChart(rf.packetsPerHour.map(h=>h.count), rf.packetsPerHour.map(h=>h.hour.slice(11)+'h'), 'var(--accent)')}
+          ${(() => {
+            const pph = rf.packetsPerHour;
+            const counts = pph.map(h => h.count);
+            // Decimate x-axis labels to avoid overlap
+            const totalHours = pph.length;
+            // Pick label interval: <=24h show every 6h, <=72h every 12h, else every 24h
+            const labelInterval = totalHours <= 24 ? 6 : totalHours <= 72 ? 12 : 24;
+            const labels = pph.map((h, i) => {
+              const hh = h.hour.slice(11, 13); // "HH"
+              const hourNum = parseInt(hh, 10);
+              if (hourNum % labelInterval === 0) {
+                // For multi-day ranges, show date on 00h boundaries
+                if (totalHours > 48 && hourNum === 0) return h.hour.slice(5, 10);
+                return hh + 'h';
+              }
+              return ''; // skip label
+            });
+            return barChart(counts, labels, 'var(--accent)');
+          })()}
         </div>
       </div>
 
@@ -622,14 +642,13 @@
     if (!data || !data.rings.length) return '<div class="text-muted">No path data for this observer</div>';
     let html = `<div class="reach-rings">`;
     data.rings.forEach(ring => {
-      const opacity = Math.max(0.3, 1 - ring.hops * 0.06);
       const nodeLinks = ring.nodes.slice(0, 8).map(n => {
         const label = n.name ? `<a href="#/nodes/${encodeURIComponent(n.pubkey)}" class="analytics-link">${esc(n.name)}</a>` : `<span class="mono">${n.hop}</span>`;
         const detail = n.distRange ? ` <span class="text-muted">(${n.distRange})</span>` : '';
         return label + detail;
       }).join(', ');
       const extra = ring.nodes.length > 8 ? ` <span class="text-muted">+${ring.nodes.length - 8} more</span>` : '';
-      html += `<div class="reach-ring" style="opacity:${opacity}">
+      html += `<div class="reach-ring">
         <div class="reach-hop">${ring.hops} hop${ring.hops > 1 ? 's' : ''}</div>
         <div class="reach-nodes">${nodeLinks}${extra}</div>
         <div class="reach-count">${ring.nodes.length} node${ring.nodes.length > 1 ? 's' : ''}</div>
@@ -673,7 +692,6 @@
     });
     let html = '<div class="reach-rings">';
     Object.entries(byDist).sort((a, b) => +a[0] - +b[0]).forEach(([dist, nodes]) => {
-      const opacity = Math.max(0.3, 1 - (+dist) * 0.06);
       const nodeLinks = nodes.slice(0, 10).map(n => {
         const label = n.name
           ? `<a href="#/nodes/${encodeURIComponent(n.pubkey)}" class="analytics-link">${esc(n.name)}</a>`
@@ -681,7 +699,7 @@
         return label + ` <span class="text-muted">via ${esc(n.observer_name)}</span>`;
       }).join(', ');
       const extra = nodes.length > 10 ? ` <span class="text-muted">+${nodes.length - 10} more</span>` : '';
-      html += `<div class="reach-ring" style="opacity:${opacity}">
+      html += `<div class="reach-ring">
         <div class="reach-hop">${dist} hop${+dist > 1 ? 's' : ''}</div>
         <div class="reach-nodes">${nodeLinks}${extra}</div>
         <div class="reach-count">${nodes.length} node${nodes.length > 1 ? 's' : ''}</div>
@@ -838,29 +856,44 @@
     }
   }
 
+  var CHANNEL_TIMELINE_MAX_SERIES = 8;
+
   function renderChannelTimeline(data) {
     if (!data.length) return '<div class="text-muted">No data</div>';
     var hours = []; var hourSet = {};
     var channelList = []; var channelSet = {};
     var lookup = {};
-    var maxCount = 1;
+    var channelVolume = {};
     for (var i = 0; i < data.length; i++) {
       var d = data[i];
       if (!hourSet[d.hour]) { hourSet[d.hour] = 1; hours.push(d.hour); }
       if (!channelSet[d.channel]) { channelSet[d.channel] = 1; channelList.push(d.channel); }
       lookup[d.hour + '|' + d.channel] = d.count;
-      if (d.count > maxCount) maxCount = d.count;
+      channelVolume[d.channel] = (channelVolume[d.channel] || 0) + d.count;
     }
     hours.sort();
+    // Sort channels by total volume descending, cap to top N
+    channelList.sort(function(a, b) { return channelVolume[b] - channelVolume[a]; });
+    var hiddenCount = Math.max(0, channelList.length - CHANNEL_TIMELINE_MAX_SERIES);
+    var visibleChannels = channelList.slice(0, CHANNEL_TIMELINE_MAX_SERIES);
+
+    var maxCount = 1;
+    for (var vi = 0; vi < visibleChannels.length; vi++) {
+      for (var hi2 = 0; hi2 < hours.length; hi2++) {
+        var c = lookup[hours[hi2] + '|' + visibleChannels[vi]] || 0;
+        if (c > maxCount) maxCount = c;
+      }
+    }
+
     var colors = ['#ef4444','#22c55e','#3b82f6','#f59e0b','#8b5cf6','#ec4899','#14b8a6','#64748b'];
     var w = 600, h = 180, pad = 35;
     var xScale = (w - pad * 2) / Math.max(hours.length - 1, 1);
     var yScale = (h - pad * 2) / maxCount;
     var svg = '<svg viewBox="0 0 ' + w + ' ' + h + '" style="width:100%;max-height:180px" role="img" aria-label="Channel message activity over time"><title>Channel message activity over time</title>';
-    for (var ci = 0; ci < channelList.length; ci++) {
+    for (var ci = 0; ci < visibleChannels.length; ci++) {
       var pts = [];
       for (var hi = 0; hi < hours.length; hi++) {
-        var count = lookup[hours[hi] + '|' + channelList[ci]] || 0;
+        var count = lookup[hours[hi] + '|' + visibleChannels[ci]] || 0;
         var x = pad + hi * xScale;
         var y = h - pad - count * yScale;
         pts.push(x + ',' + y);
@@ -874,8 +907,11 @@
     }
     svg += '</svg>';
     var legendParts = [];
-    for (var lci = 0; lci < channelList.length; lci++) {
-      legendParts.push('<span><span class="legend-dot" style="background:' + colors[lci % colors.length] + '"></span>' + esc(channelList[lci]) + '</span>');
+    for (var lci = 0; lci < visibleChannels.length; lci++) {
+      legendParts.push('<span><span class="legend-dot" style="background:' + colors[lci % colors.length] + '"></span>' + esc(visibleChannels[lci]) + '</span>');
+    }
+    if (hiddenCount > 0) {
+      legendParts.push('<span class="text-muted">+' + hiddenCount + ' more</span>');
     }
     svg += '<div class="timeline-legend">' + legendParts.join('') + '</div>';
     return svg;
@@ -998,6 +1034,7 @@
       return (filtered.length ? '<table class="analytics-table" id="mbAdoptersTable" style="margin-top:12px">' +
           '<thead><tr>' +
             '<th scope="col" data-sort="name">Node</th>' +
+            '<th scope="col" data-sort="role">Role</th>' +
             '<th scope="col" data-sort="status">Status</th>' +
             '<th scope="col" data-sort="hashSize">Hash Size</th>' +
             '<th scope="col" data-sort="packets">Adverts</th>' +
@@ -1005,8 +1042,10 @@
           '</tr></thead>' +
           '<tbody>' +
             filtered.map(function(r) {
+              var roleColor = (window.ROLE_COLORS || {})[r.role] || '#6b7280';
               return '<tr class="clickable-row" data-action="navigate" data-value="#/nodes/' + encodeURIComponent(r.pubkey) + '" tabindex="0" role="row">' +
                 '<td><strong>' + esc(r.name) + '</strong></td>' +
+                '<td><span class="badge" style="background:' + roleColor + '20;color:' + roleColor + '">' + esc(r.role || 'unknown') + '</span></td>' +
                 '<td><span style="color:' + (statusColor[r.status] || statusColor.unknown) + '">' +
                   (statusIcon[r.status] || '❓') + ' ' + (statusLabel[r.status] || 'Unknown') + '</span></td>' +
                 '<td><span class="badge badge-hash-' + r.hashSize + '">' + r.hashSize + '-byte</span></td>' +
@@ -1190,10 +1229,10 @@
         else matrixDesc.textContent = '3-byte prefix space is too large to visualize as a matrix — collision table is shown below.';
       }
       renderHashMatrixFromServer(cData.by_size[String(bytes)], bytes);
-      // Hide collision risk card for 3-byte — stats are shown in the matrix panel
+      // Show collision risk section for all byte sizes
       const riskCard = document.getElementById('collisionRiskSection');
-      if (riskCard) riskCard.style.display = bytes === 3 ? 'none' : '';
-      if (bytes !== 3) renderCollisionsFromServer(cData.by_size[String(bytes)], bytes);
+      if (riskCard) riskCard.style.display = '';
+      renderCollisionsFromServer(cData.by_size[String(bytes)], bytes);
     }
 
     // Wire up selector
@@ -1285,9 +1324,9 @@
         <div class="analytics-stat-value" style="font-size:16px">${pctStr}%</div>
         <div style="font-size:10px;color:var(--text-muted);margin-top:2px">${usedCount > 256 ? usedCount + ' of ' : 'of '}${spaceLabel} possible</div>
       </div>
-      <div class="analytics-stat-card" style="flex:1;min-width:110px;border-color:${collisionCount > 0 ? 'var(--status-red)' : 'var(--border)'}">
+      <div class="analytics-stat-card" style="flex:1;min-width:110px;border-color:${collisionCount > 0 ? 'var(--status-red)' : 'var(--border)'}${collisionCount > 0 ? ';cursor:pointer' : ''}" ${collisionCount > 0 ? 'onclick="document.getElementById(\'collisionRiskSection\')?.scrollIntoView({behavior:\'smooth\',block:\'start\'})"' : ''} ${collisionCount > 0 ? 'title="Click to see collision details"' : ''}>
         <div class="analytics-stat-label">Prefix collisions</div>
-        <div class="analytics-stat-value" style="color:${collisionCount > 0 ? 'var(--status-red)' : 'var(--status-green)'}">${collisionCount}</div>
+        <div class="analytics-stat-value" style="color:${collisionCount > 0 ? 'var(--status-red)' : 'var(--status-green)'}">${collisionCount}${collisionCount > 0 ? ' <span style="font-size:11px;opacity:0.7">▼</span>' : ''}</div>
       </div>
     </div>`;
   }
@@ -1362,7 +1401,7 @@
     // 3-byte: show a summary panel instead of a matrix
     if (bytes === 3) {
       el.innerHTML = hashStatCardsHtml(totalNodes, stats.using_this_size || 0, '3-byte', 16777216, stats.unique_prefixes || 0, stats.collision_count || 0) +
-        `<p class="text-muted" style="margin:0;font-size:0.8em">The 3-byte prefix space (16.7M values) is too large to visualize as a grid.</p>` +
+        `<p class="text-muted" style="margin:0;font-size:0.8em">The 3-byte prefix space (16.7M values) is too large to visualize as a grid.${(stats.collision_count || 0) > 0 ? ' See collision details below.' : ''}</p>` +
         `<p class="text-muted" style="margin:8px 0 0;font-size:0.8em">ℹ️ This tab only counts collisions among repeaters configured for this hash size. The <a href="#/analytics?tab=prefix-tool" style="color:var(--accent)">Prefix Tool</a> checks all repeaters regardless of configured hash size.</p>`;
       return;
     }
@@ -1932,15 +1971,18 @@
       }
 
       // Top hops leaderboard
-      html += `<div class="analytics-section"><h3>🏆 Top 20 Longest Hops</h3><table class="data-table"><thead><tr><th scope="col">#</th><th scope="col">From</th><th scope="col">To</th><th scope="col">Distance (${distUnitLabel})</th><th scope="col">Type</th><th scope="col">SNR</th><th scope="col">Packet</th><th scope="col"></th></tr></thead><tbody>`;
+      html += `<div class="analytics-section"><h3>🏆 Top 20 Longest Hops</h3><table class="data-table"><thead><tr><th scope="col">#</th><th scope="col">From</th><th scope="col">To</th><th scope="col">Distance (${distUnitLabel})</th><th scope="col">Type</th><th scope="col">Obs</th><th scope="col">Best SNR</th><th scope="col">Median SNR</th><th scope="col">Packet</th><th scope="col"></th></tr></thead><tbody>`;
       const top20 = data.topHops.slice(0, 20);
       top20.forEach((h, i) => {
         const fromLink = h.fromPk ? `<a href="#/nodes/${encodeURIComponent(h.fromPk)}" class="analytics-link">${esc(h.fromName)}</a>` : esc(h.fromName || '?');
         const toLink = h.toPk ? `<a href="#/nodes/${encodeURIComponent(h.toPk)}" class="analytics-link">${esc(h.toName)}</a>` : esc(h.toName || '?');
-        const snr = h.snr != null ? h.snr + ' dB' : '<span class="text-muted">—</span>';
+        const bestSnr = h.bestSnr != null ? Number(h.bestSnr).toFixed(1) + ' dB' : '<span class="text-muted">—</span>';
+        const medianSnr = h.medianSnr != null ? Number(h.medianSnr).toFixed(1) + ' dB' : '<span class="text-muted">—</span>';
+        const obs = h.obsCount != null ? h.obsCount : 1;
         const pktLink = h.hash ? `<a href="#/packet/${encodeURIComponent(h.hash)}" class="analytics-link mono" style="font-size:0.85em">${esc(h.hash.slice(0, 12))}…</a>` : '—';
         const mapBtn = h.fromPk && h.toPk ? `<button class="btn-icon dist-map-hop" data-from="${esc(h.fromPk)}" data-to="${esc(h.toPk)}" title="View on map">🗺️</button>` : '';
-        html += `<tr><td>${i+1}</td><td>${fromLink}</td><td>${toLink}</td><td><strong>${formatDistance(h.dist)}</strong></td><td>${esc(h.type)}</td><td>${snr}</td><td>${pktLink}</td><td>${mapBtn}</td></tr>`;
+        const tsTitle = h.timestamp ? `Best observation: ${h.timestamp}` : '';
+        html += `<tr title="${esc(tsTitle)}"><td>${i+1}</td><td>${fromLink}</td><td>${toLink}</td><td><strong>${formatDistance(h.dist)}</strong></td><td>${esc(h.type)}</td><td>${obs}</td><td>${bestSnr}</td><td>${medianSnr}</td><td>${pktLink}</td><td>${mapBtn}</td></tr>`;
       });
       html += `</tbody></table></div>`;
 
@@ -1995,6 +2037,8 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
     window._analyticsRfNFColumnChart = rfNFColumnChart;
     window._analyticsRenderMultiByteCapability = renderMultiByteCapability;
     window._analyticsRenderMultiByteAdopters = renderMultiByteAdopters;
+    window._analyticsHashStatCardsHtml = hashStatCardsHtml;
+    window._analyticsRenderCollisionsFromServer = renderCollisionsFromServer;
   }
 
   // ─── Neighbor Graph Tab ─────────────────────────────────────────────────────
@@ -2009,8 +2053,8 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
           <label style="font-size:13px">Roles:
             <span id="ngRoleChecks" style="margin-left:4px"></span>
           </label>
-          <label style="font-size:13px">Min Score: <input type="range" id="ngMinScore" min="0" max="100" value="10" style="width:100px;vertical-align:middle">
-            <span id="ngMinScoreVal">0.10</span>
+          <label style="font-size:13px">Min Score: <input type="range" id="ngMinScore" min="0" max="100" value="70" style="width:100px;vertical-align:middle">
+            <span id="ngMinScoreVal">0.70</span>
           </label>
           <label style="font-size:13px">Confidence:
             <select id="ngConfidence" style="font-size:12px;padding:2px 4px">
@@ -2038,6 +2082,11 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
       const color = (window.ROLE_COLORS || {})[r] || '#888';
       rcEl.innerHTML += `<label style="font-size:12px;margin-right:8px"><input type="checkbox" data-role="${r}" checked> <span style="color:${esc(color)}">${esc(r)}</span></label>`;
     });
+    // Observer checkbox — unchecked by default (observers create hub-and-spoke noise)
+    {
+      const color = (window.ROLE_COLORS || {}).observer || '#8b5cf6';
+      rcEl.innerHTML += `<label style="font-size:12px;margin-right:8px"><input type="checkbox" data-role="observer"> <span style="color:${esc(color)}">observer</span></label>`;
+    }
 
     // Load data
     const rqs = RegionFilter.regionQueryString();
@@ -2055,8 +2104,17 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
     startGraphRenderer();
 
     // Filter listeners
+    // Restore saved min score from localStorage
+    var savedScore = localStorage.getItem('ng-min-score');
+    if (savedScore !== null) {
+      document.getElementById('ngMinScore').value = savedScore;
+      document.getElementById('ngMinScoreVal').textContent = (savedScore / 100).toFixed(2);
+      applyNGFilters();
+    }
+
     document.getElementById('ngMinScore').addEventListener('input', function() {
       document.getElementById('ngMinScoreVal').textContent = (this.value / 100).toFixed(2);
+      localStorage.setItem('ng-min-score', this.value);
       applyNGFilters();
     });
     document.getElementById('ngConfidence').addEventListener('change', applyNGFilters);
@@ -2095,7 +2153,7 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
     // Filter nodes by role
     const visibleNodes = _ngState.allNodes.filter(n => {
       const role = (n.role || 'unknown').toLowerCase();
-      return checkedRoles.has(role) || role === 'unknown' || role === 'observer';
+      return checkedRoles.has(role) || role === 'unknown';
     });
     const visiblePKs = new Set(visibleNodes.map(n => n.pubkey));
 
@@ -3402,5 +3460,112 @@ function destroy() { _analyticsData = {}; _channelData = null; if (_ngState && _
     return svg;
   }
 
+  // #690 — Clock Health fleet view (M3)
+  async function renderClockHealthTab(el) {
+    el.innerHTML = '<div class="text-center text-muted" style="padding:40px">Loading clock health data…</div>';
+    try {
+      var data = await (await fetch('/api/nodes/clock-skew')).json();
+      if (!Array.isArray(data) || !data.length) {
+        el.innerHTML = '<div class="text-center text-muted" style="padding:40px">No clock skew data available. Nodes need recent adverts for clock analysis.</div>';
+        return;
+      }
+
+      // State
+      var activeFilter = 'all';
+      var sortKey = 'severity';
+      var sortDir = 'asc'; // severity worst-first
+
+      function render() {
+        // Filter
+        var filtered = activeFilter === 'all' ? data : data.filter(function(n) { return n.severity === activeFilter; });
+
+        // Sort
+        filtered = filtered.slice().sort(function(a, b) {
+          var v;
+          if (sortKey === 'severity') {
+            v = (SKEW_SEVERITY_ORDER[a.severity] || 9) - (SKEW_SEVERITY_ORDER[b.severity] || 9);
+          } else if (sortKey === 'skew') {
+            v = Math.abs(window.currentSkewValue(b) || 0) - Math.abs(window.currentSkewValue(a) || 0);
+          } else if (sortKey === 'name') {
+            v = (a.nodeName || '').localeCompare(b.nodeName || '');
+          } else if (sortKey === 'drift') {
+            v = Math.abs(b.driftPerDaySec || 0) - Math.abs(a.driftPerDaySec || 0);
+          }
+          return sortDir === 'desc' ? -v : v;
+        });
+
+        // Summary
+        var counts = { ok: 0, warning: 0, critical: 0, absurd: 0 };
+        data.forEach(function(n) { if (counts[n.severity] !== undefined) counts[n.severity]++; });
+
+        // Filter buttons (also serve as summary — no separate stats pills needed)
+        var filterColors = { ok: 'var(--status-green)', warning: 'var(--status-yellow)', critical: 'var(--status-orange)', absurd: 'var(--status-purple)', no_clock: 'var(--text-muted)' };
+        var filters = ['all', 'ok', 'warning', 'critical', 'absurd', 'no_clock'];
+        var filterHtml = '<div style="margin-bottom:10px">' + filters.map(function(f) {
+          var dot = f !== 'all' ? '<span style="display:inline-block;width:8px;height:8px;border-radius:50%;background:' + filterColors[f] + ';margin-right:4px;vertical-align:middle"></span>' : '';
+          return '<button class="clock-filter-btn' + (activeFilter === f ? ' active' : '') + '" data-filter="' + f + '">' +
+            dot + (f === 'all' ? 'All (' + data.length + ')' : (SKEW_SEVERITY_LABELS[f] || f) + ' (' + (counts[f] || 0) + ')') +
+            '</button>';
+        }).join('') + '</div>';
+
+        // Table
+        var rowsHtml = filtered.map(function(n) {
+          var rowClass = 'clock-fleet-row--' + (n.severity || 'ok');
+          var lastAdv = n.lastObservedTS ? new Date(n.lastObservedTS * 1000).toISOString().replace('T', ' ').replace(/\.\d+Z/, ' UTC') : '—';
+          var skewVal = window.currentSkewValue(n);
+          var skewText = n.severity === 'no_clock' ? 'No Clock' : formatSkew(skewVal);
+          var driftText = n.severity === 'no_clock' || !n.driftPerDaySec ? '–' : formatDrift(n.driftPerDaySec);
+          return '<tr class="' + rowClass + '" data-pubkey="' + esc(n.pubkey) + '" style="cursor:pointer">' +
+            '<td><strong>' + esc(n.nodeName || n.pubkey.slice(0, 12)) + '</strong></td>' +
+            '<td style="font-family:var(--mono,monospace)">' + skewText + '</td>' +
+            '<td>' + renderSkewBadge(n.severity, skewVal, n) + '</td>' +
+            '<td style="font-family:var(--mono,monospace)">' + driftText + '</td>' +
+            '<td style="font-size:11px">' + lastAdv + '</td>' +
+            '</tr>';
+        }).join('');
+
+        el.innerHTML = '<h3 style="margin:0 0 10px">⏰ Clock Health</h3>' +
+          filterHtml +
+          '<table class="data-table analytics-table" id="clock-health-table">' +
+          '<thead><tr>' +
+          '<th data-sort-col="name" style="cursor:pointer">Name</th>' +
+          '<th data-sort-col="skew" style="cursor:pointer">Skew</th>' +
+          '<th data-sort-col="severity" style="cursor:pointer">Severity</th>' +
+          '<th data-sort-col="drift" style="cursor:pointer">Drift Rate</th>' +
+          '<th>Last Advert</th>' +
+          '</tr></thead><tbody>' + rowsHtml + '</tbody></table>';
+
+        // Bind filter clicks
+        el.querySelectorAll('.clock-filter-btn').forEach(function(btn) {
+          btn.addEventListener('click', function() {
+            activeFilter = btn.dataset.filter;
+            render();
+          });
+        });
+
+        // Bind header sort clicks
+        el.querySelectorAll('[data-sort-col]').forEach(function(th) {
+          th.addEventListener('click', function() {
+            var col = th.dataset.sortCol;
+            if (sortKey === col) { sortDir = sortDir === 'asc' ? 'desc' : 'asc'; }
+            else { sortKey = col; sortDir = 'asc'; }
+            render();
+          });
+        });
+
+        // Bind row clicks → navigate to node
+        el.querySelectorAll('tr[data-pubkey]').forEach(function(tr) {
+          tr.addEventListener('click', function() {
+            location.hash = '#/nodes/' + encodeURIComponent(tr.dataset.pubkey);
+          });
+        });
+      }
+
+      render();
+    } catch (err) {
+      el.innerHTML = '<div class="text-center" style="color:var(--status-red);padding:40px">Failed to load clock health data: ' + esc(String(err)) + '</div>';
+    }
+  }
+
   registerPage('analytics', { init, destroy });
 })();

public/app.js

@@ -10,6 +10,8 @@ function routeTypeName(n) { return ROUTE_TYPES[n] || 'UNKNOWN'; }
 function payloadTypeName(n) { return PAYLOAD_TYPES[n] || 'UNKNOWN'; }
 function payloadTypeColor(n) { return PAYLOAD_COLORS[n] || 'unknown'; }
 function isTransportRoute(rt) { return rt === 0 || rt === 3; }
+/** Byte offset of path_len in raw_hex: 5 for transport routes (4 bytes of next/last hop codes precede it), 1 otherwise. */
+function getPathLenOffset(routeType) { return isTransportRoute(routeType) ? 5 : 1; }
 function transportBadge(rt) { return isTransportRoute(rt) ? ' <span class="badge badge-transport" title="' + routeTypeName(rt) + '">T</span>' : ''; }
 
 // --- Utilities ---
@@ -1027,7 +1029,6 @@ function makeColumnsResizable(tableSelector, storageKey) {
   // Add resize handles
   ths.forEach((th, i) => {
     if (i === ths.length - 1) return;
-    th.style.position = 'relative';
     const handle = document.createElement('div');
     handle.className = 'col-resize-handle';
     handle.addEventListener('mousedown', (e) => {

public/channel-decrypt.js

@@ -0,0 +1,295 @@
+/**
+ * Client-side MeshCore channel decryption module.
+ *
+ * Implements the same crypto as internal/channel/channel.go:
+ *   - Key derivation: SHA-256("#channelname")[:16]
+ *   - Channel hash: SHA-256(key)[0]
+ *   - MAC: HMAC-SHA256 with 32-byte secret (key + 16 zero bytes), truncated to 2 bytes
+ *   - Encryption: AES-128-ECB (block-by-block)
+ *   - Plaintext: timestamp(4 LE) + flags(1) + "sender: message\0"
+ *
+ * Keys NEVER leave the browser. No fetch/XHR/network calls in this module.
+ */
+/* eslint-disable no-var */
+window.ChannelDecrypt = (function () {
+  'use strict';
+
+  var STORAGE_KEY = 'corescope_channel_keys';
+  var CACHE_KEY = 'corescope_channel_cache';
+
+  // ---- Hex utilities ----
+
+  function bytesToHex(bytes) {
+    var hex = '';
+    for (var i = 0; i < bytes.length; i++) {
+      hex += (bytes[i] < 16 ? '0' : '') + bytes[i].toString(16);
+    }
+    return hex;
+  }
+
+  function hexToBytes(hex) {
+    var bytes = new Uint8Array(hex.length / 2);
+    for (var i = 0; i < hex.length; i += 2) {
+      bytes[i / 2] = parseInt(hex.substring(i, i + 2), 16);
+    }
+    return bytes;
+  }
+
+  // ---- Key derivation ----
+
+  /**
+   * Derive AES-128 key from channel name: SHA-256("#channelname")[:16].
+   * @param {string} channelName - e.g. "#LongFast"
+   * @returns {Promise<Uint8Array>} 16-byte key
+   */
+  async function deriveKey(channelName) {
+    var enc = new TextEncoder();
+    var hash = await crypto.subtle.digest('SHA-256', enc.encode(channelName));
+    return new Uint8Array(hash).slice(0, 16);
+  }
+
+  /**
+   * Compute the 1-byte channel hash: SHA-256(key)[0].
+   * @param {Uint8Array} key - 16-byte key
+   * @returns {Promise<number>} single byte (0-255)
+   */
+  async function computeChannelHash(key) {
+    var hash = await crypto.subtle.digest('SHA-256', key);
+    return new Uint8Array(hash)[0];
+  }
+
+  // ---- AES-128-ECB via Web Crypto (CBC with zero IV, block-by-block) ----
+
+  /**
+   * Decrypt AES-128-ECB by decrypting each 16-byte block independently
+   * using AES-CBC with a zero IV (equivalent to ECB for single blocks).
+   * @param {Uint8Array} key - 16-byte AES key
+   * @param {Uint8Array} ciphertext - must be multiple of 16 bytes
+   * @returns {Promise<Uint8Array>} plaintext
+   */
+  async function decryptECB(key, ciphertext) {
+    if (ciphertext.length === 0 || ciphertext.length % 16 !== 0) {
+      return null;
+    }
+    var cryptoKey = await crypto.subtle.importKey(
+      'raw', key, { name: 'AES-CBC' }, false, ['decrypt']
+    );
+    var zeroIV = new Uint8Array(16);
+    var plaintext = new Uint8Array(ciphertext.length);
+
+    for (var i = 0; i < ciphertext.length; i += 16) {
+      var block = ciphertext.slice(i, i + 16);
+      // Append a dummy block (16 bytes of 0x10 = PKCS7 padding for empty next block)
+      // so Web Crypto doesn't complain about padding
+      var padded = new Uint8Array(32);
+      padded.set(block, 0);
+      // Second block is PKCS7 padding: 16 bytes of 0x10
+      for (var j = 16; j < 32; j++) padded[j] = 16;
+
+      var decrypted = await crypto.subtle.decrypt(
+        { name: 'AES-CBC', iv: zeroIV }, cryptoKey, padded
+      );
+      var decBytes = new Uint8Array(decrypted);
+      plaintext.set(decBytes.slice(0, 16), i);
+    }
+
+    return plaintext;
+  }
+
+  // ---- MAC verification ----
+
+  /**
+   * Verify HMAC-SHA256 MAC (first 2 bytes) using 32-byte secret (key + 16 zero bytes).
+   * @param {Uint8Array} key - 16-byte AES key
+   * @param {Uint8Array} ciphertext - encrypted data
+   * @param {string} macHex - 4-char hex string (2 bytes)
+   * @returns {Promise<boolean>}
+   */
+  async function verifyMAC(key, ciphertext, macHex) {
+    // Build 32-byte channel secret: key + 16 zero bytes
+    var secret = new Uint8Array(32);
+    secret.set(key, 0);
+    // remaining 16 bytes are already 0
+
+    var cryptoKey = await crypto.subtle.importKey(
+      'raw', secret, { name: 'HMAC', hash: 'SHA-256' }, false, ['sign']
+    );
+    var sig = await crypto.subtle.sign('HMAC', cryptoKey, ciphertext);
+    var sigBytes = new Uint8Array(sig);
+
+    var macBytes = hexToBytes(macHex);
+    return sigBytes[0] === macBytes[0] && sigBytes[1] === macBytes[1];
+  }
+
+  // ---- Plaintext parsing ----
+
+  /**
+   * Parse decrypted plaintext: timestamp(4 LE) + flags(1) + "sender: message\0..."
+   * @param {Uint8Array} plaintext
+   * @returns {{ timestamp: number, flags: number, sender: string, message: string } | null}
+   */
+  function parsePlaintext(plaintext) {
+    if (!plaintext || plaintext.length < 5) return null;
+
+    var timestamp = plaintext[0] | (plaintext[1] << 8) | (plaintext[2] << 16) | ((plaintext[3] << 24) >>> 0);
+    var flags = plaintext[4];
+
+    // Extract text up to first null byte
+    var textBytes = plaintext.slice(5);
+    var nullIdx = -1;
+    for (var i = 0; i < textBytes.length; i++) {
+      if (textBytes[i] === 0) { nullIdx = i; break; }
+    }
+    var text = new TextDecoder().decode(nullIdx >= 0 ? textBytes.slice(0, nullIdx) : textBytes);
+
+    // Count non-printable characters
+    var nonPrintable = 0;
+    for (var c = 0; c < text.length; c++) {
+      var code = text.charCodeAt(c);
+      if (code < 32 && code !== 10 && code !== 13 && code !== 9) nonPrintable++;
+    }
+    if (nonPrintable > 2) return null;
+
+    // Parse "sender: message" format
+    var colonIdx = text.indexOf(': ');
+    if (colonIdx > 0 && colonIdx < 50) {
+      var potentialSender = text.substring(0, colonIdx);
+      if (potentialSender.indexOf(':') < 0 && potentialSender.indexOf('[') < 0 && potentialSender.indexOf(']') < 0) {
+        return { timestamp: timestamp, flags: flags, sender: potentialSender, message: text.substring(colonIdx + 2) };
+      }
+    }
+
+    return { timestamp: timestamp, flags: flags, sender: '', message: text };
+  }
+
+  // ---- Full decrypt pipeline ----
+
+  /**
+   * Verify MAC, decrypt, and parse a single packet.
+   * @param {Uint8Array} keyBytes - 16-byte key
+   * @param {string} macHex - 4-char hex MAC
+   * @param {string} encryptedHex - hex-encoded ciphertext
+   * @returns {Promise<{ sender: string, message: string, timestamp: number } | null>}
+   */
+  async function decrypt(keyBytes, macHex, encryptedHex) {
+    var ciphertext = hexToBytes(encryptedHex);
+    if (ciphertext.length === 0 || ciphertext.length % 16 !== 0) return null;
+
+    var macOk = await verifyMAC(keyBytes, ciphertext, macHex);
+    if (!macOk) return null;
+
+    var plaintext = await decryptECB(keyBytes, ciphertext);
+    if (!plaintext) return null;
+
+    return parsePlaintext(plaintext);
+  }
+
+  // Alias used by channels.js
+  var decryptPacket = decrypt;
+
+  // ---- Key storage (localStorage) ----
+
+  function saveKey(channelName, keyHex) {
+    var keys = getKeys();
+    keys[channelName] = keyHex;
+    try { localStorage.setItem(STORAGE_KEY, JSON.stringify(keys)); } catch (e) { /* quota */ }
+  }
+
+  // Alias used by channels.js
+  var storeKey = saveKey;
+
+  function getKeys() {
+    try {
+      var raw = localStorage.getItem(STORAGE_KEY);
+      return raw ? JSON.parse(raw) : {};
+    } catch (e) { return {}; }
+  }
+
+  // Alias used by channels.js
+  var getStoredKeys = getKeys;
+
+  function removeKey(channelName) {
+    var keys = getKeys();
+    delete keys[channelName];
+    try { localStorage.setItem(STORAGE_KEY, JSON.stringify(keys)); } catch (e) { /* quota */ }
+    // Also clear cached messages for this channel
+    clearChannelCache(channelName);
+  }
+
+  /** Remove cached messages for a specific channel (by name or hash). */
+  function clearChannelCache(channelKey) {
+    try {
+      var cache = JSON.parse(localStorage.getItem(CACHE_KEY) || '{}');
+      delete cache[channelKey];
+      localStorage.setItem(CACHE_KEY, JSON.stringify(cache));
+    } catch (e) { /* quota */ }
+  }
+
+  // ---- Message cache (localStorage) ----
+
+  function cacheMessages(channelHash, messages) {
+    try {
+      var cache = JSON.parse(localStorage.getItem(CACHE_KEY) || '{}');
+      cache[channelHash] = { messages: messages, ts: Date.now() };
+      localStorage.setItem(CACHE_KEY, JSON.stringify(cache));
+    } catch (e) { /* quota */ }
+  }
+
+  function getCachedMessages(channelHash) {
+    try {
+      var cache = JSON.parse(localStorage.getItem(CACHE_KEY) || '{}');
+      var entry = cache[channelHash];
+      return entry ? entry.messages : null;
+    } catch (e) { return null; }
+  }
+
+  // Cache with lastTimestamp and count (used by channels.js via getCache/setCache)
+  var MAX_CACHED_MESSAGES = 1000;
+
+  function setCache(key, messages, lastTimestamp, totalCount) {
+    try {
+      // Enforce cache size limit: only keep most recent MAX_CACHED_MESSAGES
+      var toStore = messages;
+      if (messages.length > MAX_CACHED_MESSAGES) {
+        toStore = messages.slice(messages.length - MAX_CACHED_MESSAGES);
+      }
+      var cache = JSON.parse(localStorage.getItem(CACHE_KEY) || '{}');
+      cache[key] = {
+        messages: toStore,
+        lastTimestamp: lastTimestamp,
+        count: totalCount || toStore.length,
+        ts: Date.now()
+      };
+      localStorage.setItem(CACHE_KEY, JSON.stringify(cache));
+    } catch (e) { /* quota */ }
+  }
+
+  function getCache(key) {
+    try {
+      var cache = JSON.parse(localStorage.getItem(CACHE_KEY) || '{}');
+      return cache[key] || null;
+    } catch (e) { return null; }
+  }
+
+  return {
+    deriveKey: deriveKey,
+    decrypt: decrypt,
+    decryptPacket: decryptPacket,
+    decryptECB: decryptECB,
+    verifyMAC: verifyMAC,
+    parsePlaintext: parsePlaintext,
+    computeChannelHash: computeChannelHash,
+    bytesToHex: bytesToHex,
+    hexToBytes: hexToBytes,
+    saveKey: saveKey,
+    storeKey: storeKey,
+    getKeys: getKeys,
+    getStoredKeys: getStoredKeys,
+    removeKey: removeKey,
+    clearChannelCache: clearChannelCache,
+    cacheMessages: cacheMessages,
+    getCachedMessages: getCachedMessages,
+    setCache: setCache,
+    getCache: getCache
+  };
+})();

public/channels.js

@@ -318,6 +318,290 @@
 
   let regionChangeHandler = null;
 
+  // --- Client-side channel decryption (#725 M2) ---
+
+  // Check if input is a valid hex string (32 hex chars = 16 bytes)
+  function isHexKey(val) {
+    return /^[0-9a-fA-F]{32}$/.test(val);
+  }
+
+  // Show status message in the add-channel form (#759)
+  var statusTimer = null;
+  function showAddStatus(msg, type) {
+    var el = document.getElementById('chAddStatus');
+    if (!el) return;
+    el.textContent = msg;
+    el.className = 'ch-add-status ch-add-status--' + (type || 'info');
+    el.style.display = '';
+    clearTimeout(statusTimer);
+    if (type !== 'loading') {
+      statusTimer = setTimeout(function () { el.style.display = 'none'; }, 5000);
+    }
+  }
+
+  // Add a user channel by name (#channelname) or hex key
+  async function addUserChannel(val) {
+    var displayName = val.startsWith('#') ? val : (isHexKey(val) ? val.substring(0, 8) + '…' : '#' + val);
+    showAddStatus('Decrypting ' + displayName + ' messages…', 'loading');
+    var channelName, keyHex;
+    try {
+      if (val.startsWith('#')) {
+        channelName = val;
+        var keyBytes = await ChannelDecrypt.deriveKey(channelName);
+        keyHex = ChannelDecrypt.bytesToHex(keyBytes);
+      } else if (isHexKey(val)) {
+        keyHex = val.toLowerCase();
+        channelName = 'psk:' + keyHex.substring(0, 8);
+      } else {
+        // Try with # prefix if user forgot
+        channelName = '#' + val;
+        var keyBytes2 = await ChannelDecrypt.deriveKey(channelName);
+        keyHex = ChannelDecrypt.bytesToHex(keyBytes2);
+      }
+
+      ChannelDecrypt.storeKey(channelName, keyHex);
+
+      // Compute channel hash byte to find matching encrypted channels
+      var keyBytes3 = ChannelDecrypt.hexToBytes(keyHex);
+      var hashByte = await ChannelDecrypt.computeChannelHash(keyBytes3);
+
+      // Add to sidebar or merge with existing encrypted channel
+      mergeUserChannels();
+      renderChannelList();
+
+      // Auto-select and start decrypting
+      var targetHash = 'user:' + channelName;
+      // Check if there's an existing encrypted channel with this hash byte
+      var existingEncrypted = channels.find(function (ch) {
+        return ch.encrypted && String(ch.hash) === String(hashByte);
+      });
+      if (existingEncrypted) {
+        targetHash = existingEncrypted.hash;
+      }
+      await selectChannel(targetHash, { userKey: keyHex, channelHashByte: hashByte, channelName: channelName });
+
+      // Show success feedback (#759)
+      var msgCount = document.querySelectorAll('#chMessages .ch-msg').length;
+      var userDisplay = channelName.startsWith('psk:') ? 'Custom channel (' + channelName.substring(4) + ')' : channelName;
+      if (msgCount > 0) {
+        showAddStatus('Added ' + userDisplay + ' — ' + msgCount + ' messages decrypted', 'success');
+      } else {
+        showAddStatus('No messages found for ' + userDisplay, 'warn');
+      }
+    } catch (err) {
+      showAddStatus('Failed to decrypt', 'error');
+    }
+  }
+
+  // Merge user-stored keys into the channel list
+  function mergeUserChannels() {
+    var keys = ChannelDecrypt.getStoredKeys();
+    var names = Object.keys(keys);
+    for (var i = 0; i < names.length; i++) {
+      var name = names[i];
+      // Check if channel already exists by name
+      var exists = channels.some(function (ch) {
+        return ch.name === name || ch.hash === name || ch.hash === ('user:' + name);
+      });
+      if (!exists) {
+        channels.push({
+          hash: 'user:' + name,
+          name: name,
+          messageCount: 0,
+          lastActivityMs: 0,
+          lastSender: '',
+          lastMessage: 'Encrypted — click to decrypt',
+          encrypted: true,
+          userAdded: true
+        });
+      }
+    }
+  }
+
+  // Fetch and decrypt GRP_TXT packets client-side (M5: delta fetch + cache)
+  async function fetchAndDecryptChannel(keyHex, channelHashByte, channelName, opts) {
+    opts = opts || {};
+    var keyBytes = ChannelDecrypt.hexToBytes(keyHex);
+
+    // M5: Check cache first — serve cached messages immediately
+    var cacheKey = channelName || String(channelHashByte);
+    var cached = ChannelDecrypt.getCache(cacheKey);
+    var cachedMsgs = cached ? cached.messages : [];
+    var lastTs = cached ? cached.lastTimestamp : '';
+    var cachedCount = cached ? (cached.count || 0) : 0;
+
+    // If we have cached messages and caller wants instant render, return them first
+    if (cachedMsgs.length > 0 && !opts.forceFullDecrypt) {
+      // Signal caller to render cache immediately, then do delta fetch
+      if (opts.onCacheHit) opts.onCacheHit(cachedMsgs);
+    }
+
+    // Fetch packets from API — get all payload_type=5 (GRP_TXT/CHAN)
+    var rp = RegionFilter.getRegionParam();
+    var qs = rp ? '&region=' + encodeURIComponent(rp) : '';
+    var data;
+    try {
+      data = await api('/packets?limit=1000&payloadType=5' + qs, { ttl: 10000 });
+    } catch (e) {
+      return { messages: cachedMsgs, error: 'Failed to fetch packets: ' + e.message, fromCache: cachedMsgs.length > 0 };
+    }
+
+    var packets = data.packets || [];
+    // Filter for GRP_TXT (encrypted) packets matching our channel hash byte
+    var candidates = [];
+    for (var i = 0; i < packets.length; i++) {
+      var p = packets[i];
+      var dj;
+      try { dj = typeof p.decoded_json === 'string' ? JSON.parse(p.decoded_json) : p.decoded_json; }
+      catch (e) { continue; }
+      if (!dj) continue;
+
+      if (dj.type === 'CHAN' && dj.channel === channelName) {
+        candidates.push({ type: 'already_decrypted', decoded: dj, packet: p });
+      } else if (dj.type === 'GRP_TXT' && dj.encryptedData && dj.mac) {
+        if (dj.channelHash === channelHashByte) {
+          candidates.push({ type: 'encrypted', decoded: dj, packet: p });
+        }
+      }
+    }
+
+    // M5: Cache invalidation — if total candidate count changed, re-decrypt everything
+    var totalCandidates = candidates.length;
+    var needFullDecrypt = (totalCandidates !== cachedCount) || opts.forceFullDecrypt;
+
+    // M5: Delta fetch — only decrypt packets newer than lastTs
+    if (!needFullDecrypt && cachedMsgs.length > 0 && lastTs) {
+      // Filter candidates to only those newer than cached lastTimestamp
+      var newCandidates = candidates.filter(function (c) {
+        var ts = c.packet.first_seen || c.packet.timestamp || '';
+        return ts > lastTs;
+      });
+
+      if (newCandidates.length === 0) {
+        // Nothing new — return cache as-is
+        return { messages: cachedMsgs, fromCache: true };
+      }
+
+      // Decrypt only new candidates
+      var newDecrypted = await decryptCandidates(keyBytes, newCandidates);
+      if (newDecrypted.wrongKey) {
+        return { messages: cachedMsgs, wrongKey: true };
+      }
+
+      // Merge: cached + new, deduplicate by packetHash, sort chronologically
+      var merged = deduplicateAndMerge(cachedMsgs, newDecrypted.messages);
+      var newLastTs = merged.length ? merged[merged.length - 1].timestamp : lastTs;
+      ChannelDecrypt.setCache(cacheKey, merged, newLastTs, totalCandidates);
+      return { messages: merged, deltaCount: newDecrypted.messages.length };
+    }
+
+    if (candidates.length === 0) {
+      return { messages: cachedMsgs, empty: true };
+    }
+
+    // Full decrypt
+    var result = await decryptCandidates(keyBytes, candidates);
+    if (result.wrongKey) {
+      return { messages: result.messages, wrongKey: true };
+    }
+
+    var decrypted = result.messages;
+    // Sort chronologically (oldest first)
+    decrypted.sort(function (a, b) {
+      var ta = a.timestamp || '';
+      var tb = b.timestamp || '';
+      return ta.localeCompare(tb);
+    });
+
+    // M5: Cache results
+    var newLastTimestamp = decrypted.length ? decrypted[decrypted.length - 1].timestamp : '';
+    ChannelDecrypt.setCache(cacheKey, decrypted, newLastTimestamp, totalCandidates);
+
+    return { messages: decrypted };
+  }
+
+  /** Decrypt an array of candidate packets. Returns { messages, wrongKey }. */
+  async function decryptCandidates(keyBytes, candidates) {
+    // Sort newest first for progressive rendering
+    candidates.sort(function (a, b) {
+      var ta = a.packet.first_seen || a.packet.timestamp || '';
+      var tb = b.packet.first_seen || b.packet.timestamp || '';
+      return tb.localeCompare(ta);
+    });
+
+    var decrypted = [];
+    var macFailCount = 0;
+    var macCheckCount = 0;
+
+    for (var j = 0; j < candidates.length; j++) {
+      var c = candidates[j];
+
+      if (c.type === 'already_decrypted') {
+        var d = c.decoded;
+        var sender = d.sender || 'Unknown';
+        var text = d.text || '';
+        var ci = text.indexOf(': ');
+        if (ci > 0 && ci < 50 && text.substring(0, ci) === sender) {
+          text = text.substring(ci + 2);
+        }
+        decrypted.push({
+          sender: sender, text: text,
+          timestamp: c.packet.first_seen || c.packet.timestamp,
+          sender_timestamp: d.sender_timestamp || null,
+          packetHash: c.packet.hash, packetId: c.packet.id,
+          hops: d.path_len || 0, snr: c.packet.snr || null,
+          observers: c.packet.observer_name ? [c.packet.observer_name] : [],
+          repeats: 1
+        });
+        continue;
+      }
+
+      macCheckCount++;
+      var result = await ChannelDecrypt.decryptPacket(keyBytes, c.decoded.mac, c.decoded.encryptedData);
+      if (result) {
+        macFailCount = 0;
+        decrypted.push({
+          sender: result.sender, text: result.message,
+          timestamp: c.packet.first_seen || c.packet.timestamp,
+          sender_timestamp: result.timestamp || null,
+          packetHash: c.packet.hash, packetId: c.packet.id,
+          hops: 0, snr: c.packet.snr || null,
+          observers: c.packet.observer_name ? [c.packet.observer_name] : [],
+          repeats: 1
+        });
+      } else {
+        macFailCount++;
+        if (macCheckCount >= 10 && macFailCount >= macCheckCount) {
+          return { messages: decrypted, wrongKey: true };
+        }
+      }
+    }
+
+    return { messages: decrypted, wrongKey: false };
+  }
+
+  /** Merge cached and new messages, deduplicate by packetHash, sort chronologically. */
+  function deduplicateAndMerge(cached, newMsgs) {
+    var seen = {};
+    var merged = [];
+    // Add cached first
+    for (var i = 0; i < cached.length; i++) {
+      var key = cached[i].packetHash || ('idx:' + i);
+      if (!seen[key]) { seen[key] = true; merged.push(cached[i]); }
+    }
+    // Add new
+    for (var j = 0; j < newMsgs.length; j++) {
+      var key2 = newMsgs[j].packetHash || ('new:' + j);
+      if (!seen[key2]) { seen[key2] = true; merged.push(newMsgs[j]); }
+    }
+    merged.sort(function (a, b) {
+      var ta = a.timestamp || '';
+      var tb = b.timestamp || '';
+      return ta.localeCompare(tb);
+    });
+    return merged;
+  }
+
   function init(app, routeParam) {
     var _initUrlParams = getHashParams();
     var _pendingNode = _initUrlParams.get('node');
@@ -326,6 +610,21 @@
       <div class="ch-sidebar" aria-label="Channel list">
         <div class="ch-sidebar-header">
           <div class="ch-sidebar-title"><span class="ch-icon">💬</span> Channels</div>
+          <label class="ch-encrypted-toggle" title="Show encrypted channels (no key configured)">
+            <input type="checkbox" id="chShowEncrypted"> <span class="ch-toggle-label">🔒 No key</span>
+          </label>
+        </div>
+        <div class="ch-key-input-wrap" style="padding:4px 8px">
+          <form id="chKeyForm" autocomplete="off" class="ch-add-form">
+            <div class="ch-add-row">
+              <input type="text" id="chKeyInput" class="ch-key-input"
+                     placeholder="#channelname"
+                     aria-label="Channel name or hex key" spellcheck="false">
+              <button type="submit" class="ch-add-btn" title="Add channel">+</button>
+            </div>
+            <div class="ch-add-hint">e.g. #LongFast or 32-char hex key — decrypted in your browser.</div>
+            <div id="chAddStatus" class="ch-add-status" style="display:none"></div>
+          </form>
         </div>
         <div id="chRegionFilter" class="region-filter-container" style="padding:0 8px"></div>
         <div class="ch-channel-list" id="chList" role="listbox" aria-label="Channels">
@@ -347,6 +646,17 @@
     </div>`;
 
     RegionFilter.init(document.getElementById('chRegionFilter'));
+
+    // Encrypted channels toggle (#727)
+    var showEncryptedCb = document.getElementById('chShowEncrypted');
+    var showEncrypted = localStorage.getItem('channels-show-encrypted') === 'true';
+    showEncryptedCb.checked = showEncrypted;
+    showEncryptedCb.addEventListener('change', function () {
+      showEncrypted = showEncryptedCb.checked;
+      localStorage.setItem('channels-show-encrypted', showEncrypted ? 'true' : 'false');
+      loadChannels(true);
+    });
+
     regionChangeHandler = RegionFilter.onChange(function () {
       loadChannels(true).then(async function () {
         if (!selectedHash) return;
@@ -354,8 +664,38 @@
       });
     });
 
+    // Channel key input handler (#725 M2, improved UX #759)
+    var chKeyForm = document.getElementById('chKeyForm');
+    if (chKeyForm) {
+      var submitHandler = async function (e) {
+        e.preventDefault();
+        var input = document.getElementById('chKeyInput');
+        var val = (input.value || '').trim();
+        if (!val) return;
+        input.value = '';
+        await addUserChannel(val);
+      };
+      chKeyForm.addEventListener('submit', submitHandler);
+      var chKeyInput = document.getElementById('chKeyInput');
+      if (chKeyInput) {
+        chKeyInput.addEventListener('focus', function () {
+          var st = document.getElementById('chAddStatus');
+          if (st) { st.style.display = 'none'; clearTimeout(statusTimer); statusTimer = null; }
+        });
+      }
+    }
+
+    // Auto-enable encrypted toggle if deep-linking to an encrypted channel
+    if (routeParam && routeParam.startsWith('enc_') && !showEncrypted) {
+      showEncrypted = true;
+      showEncryptedCb.checked = true;
+      localStorage.setItem('channels-show-encrypted', 'true');
+    }
+
     loadObserverRegions();
     loadChannels().then(async function () {
+      // Also load user-added encrypted channels into the sidebar
+      mergeUserChannels();
       if (routeParam) await selectChannel(routeParam);
       if (_pendingNode && _pendingNode.length < 200) await showNodeDetail(_pendingNode);
     });
@@ -403,6 +743,29 @@
 
     // Event delegation for channel selection (touch-friendly)
     document.getElementById('chList').addEventListener('click', (e) => {
+      // M4: Remove channel button
+      const removeBtn = e.target.closest('[data-remove-channel]');
+      if (removeBtn) {
+        e.stopPropagation();
+        var channelHash = removeBtn.getAttribute('data-remove-channel');
+        if (!channelHash) return;
+        var chName = channelHash.startsWith('user:') ? channelHash.substring(5) : channelHash;
+        if (!confirm('Remove channel "' + chName + '"? This will clear saved keys and cached messages.')) return;
+        ChannelDecrypt.removeKey(chName);
+        // Remove from channels array
+        channels = channels.filter(function (c) { return c.hash !== channelHash; });
+        if (selectedHash === channelHash) {
+          selectedHash = null;
+          messages = [];
+          history.replaceState(null, '', '#/channels');
+          var msgEl2 = document.getElementById('chMessages');
+          if (msgEl2) msgEl2.innerHTML = '<div class="ch-empty">Choose a channel from the sidebar to view messages</div>';
+          var header2 = document.getElementById('chHeader');
+          if (header2) header2.querySelector('.ch-header-text').textContent = 'Select a channel';
+        }
+        renderChannelList();
+        return;
+      }
       // Color dot click — open picker, don't select channel
       const dot = e.target.closest('.ch-color-dot');
       if (dot && window.ChannelColorPicker) {
@@ -652,7 +1015,11 @@
   async function loadChannels(silent) {
     try {
       const rp = RegionFilter.getRegionParam();
-      const qs = rp ? '?region=' + encodeURIComponent(rp) : '';
+      var showEnc = localStorage.getItem('channels-show-encrypted') === 'true';
+      var params = [];
+      if (rp) params.push('region=' + encodeURIComponent(rp));
+      if (showEnc) params.push('includeEncrypted=true');
+      const qs = params.length ? '?' + params.join('&') : '';
       const data = await api('/channels' + qs, { ttl: CLIENT_TTL.channels });
       channels = (data.channels || []).map(ch => {
         ch.lastActivityMs = ch.lastActivity ? new Date(ch.lastActivity).getTime() : 0;
@@ -679,27 +1046,33 @@
     });
 
     el.innerHTML = sorted.map(ch => {
-      const name = ch.name || `Channel ${formatHashHex(ch.hash)}`;
-      const color = getChannelColor(ch.hash);
+      const isEncrypted = ch.encrypted === true;
+      const name = isEncrypted ? (ch.name || 'Unknown') : (ch.name || `Channel ${formatHashHex(ch.hash)}`);
+      const color = isEncrypted ? 'var(--text-muted, #6b7280)' : getChannelColor(ch.hash);
       const time = ch.lastActivityMs ? formatSecondsAgo(Math.floor((Date.now() - ch.lastActivityMs) / 1000)) : '';
-      const preview = ch.lastSender && ch.lastMessage
-        ? `${ch.lastSender}: ${truncate(ch.lastMessage, 28)}`
-        : `${ch.messageCount} messages`;
+      const preview = isEncrypted
+        ? `${ch.messageCount} encrypted messages (no key configured)`
+        : ch.lastSender && ch.lastMessage
+          ? `${ch.lastSender}: ${truncate(ch.lastMessage, 28)}`
+          : `${ch.messageCount} messages`;
       const sel = selectedHash === ch.hash ? ' selected' : '';
-      const abbr = name.startsWith('#') ? name.slice(0, 3) : name.slice(0, 2).toUpperCase();
+      const encClass = isEncrypted ? ' ch-encrypted' : '';
+      const abbr = isEncrypted ? '🔒' : (name.startsWith('#') ? name.slice(0, 3) : name.slice(0, 2).toUpperCase());
       // Channel color dot for color picker (#674)
       const chColor = window.ChannelColors ? window.ChannelColors.get(ch.hash) : null;
       const dotStyle = chColor ? ` style="background:${chColor}"` : '';
       // Left border for assigned color
       const borderStyle = chColor ? ` style="border-left:3px solid ${chColor}"` : '';
+      // M4: Remove button for user-added channels
+      const removeBtn = ch.userAdded ? ' <button class="ch-remove-btn" data-remove-channel="' + escapeHtml(ch.hash) + '" title="Remove channel" aria-label="Remove ' + escapeHtml(name) + '">✕</button>' : '';
 
-      return `<button class="ch-item${sel}" data-hash="${ch.hash}"${borderStyle} type="button" role="option" aria-selected="${selectedHash === ch.hash ? 'true' : 'false'}" aria-label="${escapeHtml(name)}">
-        <div class="ch-badge" style="background:${color}" aria-hidden="true">${escapeHtml(abbr)}</div>
+      return `<button class="ch-item${sel}${encClass}" data-hash="${ch.hash}"${borderStyle} type="button" role="option" aria-selected="${selectedHash === ch.hash ? 'true' : 'false'}" aria-label="${escapeHtml(name)}"${isEncrypted ? ' data-encrypted="true"' : ''}>
+        <div class="ch-badge" style="background:${color}" aria-hidden="true">${isEncrypted ? '🔒' : escapeHtml(abbr)}</div>
         <div class="ch-item-body">
           <div class="ch-item-top">
             <span class="ch-item-name">${escapeHtml(name)}</span>
             <span class="ch-color-dot" data-channel="${escapeHtml(ch.hash)}"${dotStyle} title="Change channel color" aria-label="Change color for ${escapeHtml(name)}"></span>
-            <span class="ch-item-time" data-channel-hash="${ch.hash}">${time}</span>
+            <span class="ch-item-time" data-channel-hash="${ch.hash}">${time}</span>${removeBtn}
           </div>
           <div class="ch-item-preview">${escapeHtml(preview)}</div>
         </div>
@@ -707,7 +1080,7 @@
     }).join('');
   }
 
-  async function selectChannel(hash) {
+  async function selectChannel(hash, decryptOpts) {
     const rp = RegionFilter.getRegionParam() || '';
     const request = beginMessageRequest(hash, rp);
     selectedHash = hash;
@@ -722,6 +1095,110 @@
     document.querySelector('.ch-layout')?.classList.add('ch-show-main');
 
     const msgEl = document.getElementById('chMessages');
+
+    // Shared helper: fetch, decrypt, and render messages for a channel key (M5: cache-first)
+    async function decryptAndRender(keyHex, channelHashByte, channelName) {
+      msgEl.innerHTML = '<div class="ch-loading">Decrypting messages…</div>';
+      var result = await fetchAndDecryptChannel(keyHex, channelHashByte, channelName, {
+        onCacheHit: function (cachedMsgs) {
+          // M5: Render cached messages immediately while delta fetch runs
+          messages = cachedMsgs;
+          if (messages.length > 0) {
+            header.querySelector('.ch-header-text').textContent = name + ' — ' + messages.length + ' messages (cached)';
+            renderMessages();
+            scrollToBottom();
+          }
+        }
+      });
+      if (isStaleMessageRequest(request)) return true;
+      if (result.wrongKey) {
+        msgEl.innerHTML = '<div class="ch-empty ch-wrong-key">🔒 Key does not match — no messages could be decrypted</div>';
+        return true;
+      }
+      if (result.error) {
+        msgEl.innerHTML = '<div class="ch-empty">' + escapeHtml(result.error) + '</div>';
+        return true;
+      }
+      messages = result.messages || [];
+      if (messages.length === 0) {
+        msgEl.innerHTML = '<div class="ch-empty">No encrypted messages found for this channel</div>';
+      } else {
+        header.querySelector('.ch-header-text').textContent = `${name} — ${messages.length} messages (decrypted)`;
+        renderMessages();
+        scrollToBottom();
+      }
+      return true;
+    }
+
+    // Client-side decryption path (#725 M2)
+    if (decryptOpts && decryptOpts.userKey) {
+      await decryptAndRender(decryptOpts.userKey, decryptOpts.channelHashByte, decryptOpts.channelName);
+      return;
+    }
+
+    // Check if this is a user-added channel that needs decryption
+    var storedKeys = typeof ChannelDecrypt !== 'undefined' ? ChannelDecrypt.getStoredKeys() : {};
+    if (hash.startsWith('user:')) {
+      var chName = hash.substring(5);
+      if (storedKeys[chName]) {
+        var keyHex = storedKeys[chName];
+        var keyBytes = ChannelDecrypt.hexToBytes(keyHex);
+        var hashByte = await ChannelDecrypt.computeChannelHash(keyBytes);
+        await decryptAndRender(keyHex, hashByte, chName);
+        return;
+      }
+    }
+
+    // Also check if an encrypted channel hash matches a stored key
+    if (ch && ch.encrypted) {
+      for (var kn in storedKeys) {
+        var kh = storedKeys[kn];
+        var kb = ChannelDecrypt.hexToBytes(kh);
+        var hb = await ChannelDecrypt.computeChannelHash(kb);
+        if (String(hb) === String(hash) || String(ch.hash) === String(hb)) {
+          await decryptAndRender(kh, hb, kn);
+          return;
+        }
+      }
+      // #781: No matching key found — show lock message instead of fetching gibberish
+      msgEl.innerHTML = '<div class="ch-empty">🔒 This channel is encrypted and no decryption key is configured</div>';
+      return;
+    }
+
+    // #811: Deep link to a `#`-named channel that's not in the loaded list.
+    // If a stored key matches, decrypt. Otherwise we must distinguish an
+    // encrypted-no-key channel (show lock) from an unencrypted channel that
+    // simply isn't in the toggle-off list (#825 — must fall through to REST).
+    if (hash.charAt(0) === '#') {
+      if (storedKeys[hash]) {
+        var keyHex2 = storedKeys[hash];
+        var keyBytes2 = ChannelDecrypt.hexToBytes(keyHex2);
+        var hashByte2 = await ChannelDecrypt.computeChannelHash(keyBytes2);
+        await decryptAndRender(keyHex2, hashByte2, hash);
+        return;
+      }
+      // #825: confirm encrypted-ness via an encrypted-included channel list
+      // before assuming a lock state. Conservative on error — fall through.
+      // Show a loading affordance so cold deep links don't display stale content
+      // for the duration of the metadata RTT (cached 15s thereafter).
+      msgEl.innerHTML = '<div class="ch-loading">Loading messages…</div>';
+      try {
+        var rpInc = RegionFilter.getRegionParam();
+        var paramsInc = ['includeEncrypted=true'];
+        if (rpInc) paramsInc.push('region=' + encodeURIComponent(rpInc));
+        var allCh = await api('/channels?' + paramsInc.join('&'), { ttl: CLIENT_TTL.channels });
+        if (isStaleMessageRequest(request)) return;
+        var foundCh = (allCh.channels || []).find(function (c) { return c.hash === hash; });
+        if (foundCh && foundCh.encrypted === true) {
+          msgEl.innerHTML = '<div class="ch-empty">🔒 This channel is encrypted and no decryption key is configured</div>';
+          return;
+        }
+        // Unencrypted (or unknown) — fall through to the REST fetch below.
+      } catch (e) {
+        // ignore — fall through to REST fetch
+      }
+    }
+
     msgEl.innerHTML = '<div class="ch-loading">Loading messages…</div>';
 
     try {
@@ -743,6 +1220,9 @@
 
   async function refreshMessages(opts) {
     if (!selectedHash) return;
+    // Skip refresh for encrypted channels — no messages to fetch
+    var selCh = channels.find(function (c) { return c.hash === selectedHash; });
+    if (selCh && selCh.encrypted) return;
     opts = opts || {};
     const msgEl = document.getElementById('chMessages');
     if (!msgEl) return;

public/customize-v2.js

@@ -1173,6 +1173,10 @@
       '<details style="margin-top:12px"><summary style="font-size:12px;font-weight:600;cursor:pointer;color:var(--text-muted)">Raw JSON</summary>' +
         '<textarea id="cv2ExportJson" style="width:100%;min-height:200px;font-family:var(--mono);font-size:12px;background:var(--surface-1);border:1px solid var(--border);border-radius:6px;padding:12px;color:var(--text);resize:vertical;box-sizing:border-box;margin-top:8px">' + esc(json) + '</textarea>' +
       '</details>' +
+      '<p class="cust-section-title" style="margin-top:20px">Tools</p>' +
+      '<p style="font-size:12px;color:var(--text-muted);margin-bottom:10px">Server-side configuration helpers.</p>' +
+      '<a href="/geofilter-builder.html" target="_blank" style="display:inline-block;padding:7px 14px;background:var(--surface-1);border:1px solid var(--border);border-radius:6px;color:var(--accent);font-size:13px;text-decoration:none;font-weight:500">🗺️ GeoFilter Builder →</a>' +
+      '<p style="font-size:11px;color:var(--text-muted);margin-top:6px">Draw a polygon on the map to generate a <code style="font-family:var(--mono)">geo_filter</code> block for <code style="font-family:var(--mono)">config.json</code>.</p>' +
     '</div>';
   }
 

public/geofilter-builder.html

@@ -0,0 +1,170 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+<meta charset="UTF-8">
+<meta name="viewport" content="width=device-width, initial-scale=1.0">
+<title>GeoFilter Builder — CoreScope</title>
+<link rel="stylesheet" href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css"/>
+<script src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js"></script>
+<style>
+  * { box-sizing: border-box; margin: 0; padding: 0; }
+  body { font-family: system-ui, sans-serif; background: #1a1a2e; color: #e0e0e0; height: 100vh; display: flex; flex-direction: column; }
+  header { padding: 12px 16px; background: #0f0f23; border-bottom: 1px solid #333; display: flex; align-items: center; gap: 16px; flex-wrap: wrap; }
+  header h1 { font-size: 1rem; font-weight: 600; color: #4a9eff; white-space: nowrap; }
+  .controls { display: flex; gap: 8px; flex-wrap: wrap; }
+  button { padding: 6px 14px; border: none; border-radius: 6px; cursor: pointer; font-size: 0.85rem; font-weight: 500; }
+  #btnUndo  { background: #333; color: #ccc; }
+  #btnClear { background: #5a2020; color: #ffaaaa; }
+  #btnUndo:hover  { background: #444; }
+  #btnClear:hover { background: #7a2020; }
+  .hint { font-size: 0.8rem; color: #888; margin-left: auto; }
+  #map { flex: 1; }
+  #output-panel { background: #0f0f23; border-top: 1px solid #333; padding: 12px 16px; display: flex; gap: 12px; align-items: flex-start; }
+  #output-panel label { font-size: 0.75rem; color: #888; white-space: nowrap; padding-top: 6px; }
+  #output { flex: 1; background: #111; border: 1px solid #333; border-radius: 6px; padding: 10px 12px; font-family: monospace; font-size: 0.78rem; color: #7ec8e3; white-space: pre; overflow-x: auto; min-height: 54px; max-height: 140px; overflow-y: auto; cursor: text; }
+  #output.empty { color: #555; font-style: italic; }
+  #btnCopy { padding: 6px 14px; background: #1a4a7a; color: #7ec8e3; border-radius: 6px; border: none; cursor: pointer; font-size: 0.85rem; white-space: nowrap; align-self: flex-end; }
+  #btnCopy:hover { background: #2a6aaa; }
+  #btnCopy.copied { background: #1a6a3a; color: #7effa0; }
+  #counter { font-size: 0.8rem; color: #888; padding-top: 6px; white-space: nowrap; }
+  .bufferRow { display: flex; align-items: center; gap: 8px; }
+  .bufferRow label { font-size: 0.85rem; color: #aaa; }
+  .bufferRow input { width: 60px; padding: 5px 8px; background: #222; border: 1px solid #444; border-radius: 6px; color: #eee; font-size: 0.85rem; }
+  #help-bar { background: #0f0f23; padding: 6px 16px; font-size: 0.75rem; color: #666; border-top: 1px solid #222; }
+  #help-bar a { color: #4a9eff; text-decoration: none; }
+  #help-bar a:hover { text-decoration: underline; }
+  #back-link { font-size: 0.8rem; color: #4a9eff; text-decoration: none; white-space: nowrap; }
+  #back-link:hover { text-decoration: underline; }
+</style>
+</head>
+<body>
+
+<header>
+  <a href="/" id="back-link">← CoreScope</a>
+  <h1>GeoFilter Builder</h1>
+  <div class="controls">
+    <button id="btnUndo">↩ Undo</button>
+    <button id="btnClear">✕ Clear</button>
+  </div>
+  <div class="bufferRow">
+    <label for="bufferKm">Buffer km:</label>
+    <!-- Extra margin (km) outside the polygon edge that still passes the filter -->
+    <input type="number" id="bufferKm" value="20" min="0" max="500"/>
+  </div>
+  <span class="hint">Click on the map to add polygon points</span>
+</header>
+
+<div id="map"></div>
+
+<!-- Output panel: shows the geo_filter JSON block ready to paste into config.json -->
+<div id="output-panel">
+  <label>config.json</label>
+  <div id="output" class="empty">Add at least 3 points to generate config…</div>
+  <div style="display:flex;flex-direction:column;gap:8px;align-items:flex-end">
+    <span id="counter">0 points</span>
+    <button id="btnCopy">Copy</button>
+  </div>
+</div>
+
+<!-- Instructions: paste the output into config.json as a top-level "geo_filter" key, then restart the server -->
+<div id="help-bar">
+  Copy the JSON above → paste as a top-level key in <code>config.json</code> → restart the server.
+  Nodes with no GPS fix always pass through. Remove the <code>geo_filter</code> block to disable filtering.
+  &nbsp;·&nbsp; <a href="https://github.com/Kpa-clawbot/CoreScope/blob/master/docs/user-guide/geofilter.md" target="_blank">Documentation ↗</a>
+</div>
+
+<script>
+const map = L.map('map').setView([50.5, 4.4], 8);
+
+L.tileLayer('https://{s}.basemaps.cartocdn.com/dark_all/{z}/{x}/{y}{r}.png', {
+  attribution: '© OpenStreetMap © CartoDB',
+  maxZoom: 19
+}).addTo(map);
+
+let points = [];
+let markers = [];
+let polygon = null;
+let closingLine = null;
+
+function latLonPair(latlng) {
+  return [parseFloat(latlng.lat.toFixed(6)), parseFloat(latlng.lng.toFixed(6))];
+}
+
+function render() {
+  // Remove existing polygon and closing line
+  if (polygon) { map.removeLayer(polygon); polygon = null; }
+  if (closingLine) { map.removeLayer(closingLine); closingLine = null; }
+
+  if (points.length >= 3) {
+    polygon = L.polygon(points, {
+      color: '#4a9eff', weight: 2, fillColor: '#4a9eff', fillOpacity: 0.12
+    }).addTo(map);
+  } else if (points.length === 2) {
+    closingLine = L.polyline(points, { color: '#4a9eff', weight: 2, dashArray: '5,5' }).addTo(map);
+  }
+
+  updateOutput();
+}
+
+function updateOutput() {
+  const el = document.getElementById('output');
+  const counter = document.getElementById('counter');
+  counter.textContent = points.length + ' point' + (points.length !== 1 ? 's' : '');
+
+  if (points.length < 3) {
+    el.textContent = 'Add at least 3 points to generate config…';
+    el.classList.add('empty');
+    return;
+  }
+  el.classList.remove('empty');
+
+  const bufferKm = parseFloat(document.getElementById('bufferKm').value) || 0;
+  // Output format: { "geo_filter": { "bufferKm": N, "polygon": [[lat,lon], ...] } }
+  // Paste this as a top-level key in config.json
+  const config = { bufferKm, polygon: points };
+  el.textContent = JSON.stringify({ geo_filter: config }, null, 2);
+}
+
+map.on('click', function(e) {
+  const pt = latLonPair(e.latlng);
+  points.push(pt);
+
+  const idx = points.length;
+  const marker = L.circleMarker(e.latlng, {
+    radius: 6, color: '#4a9eff', weight: 2, fillColor: '#4a9eff', fillOpacity: 0.9
+  }).addTo(map).bindTooltip(String(idx), { permanent: true, direction: 'top', offset: [0, -8], className: 'pt-label' });
+  markers.push(marker);
+
+  render();
+});
+
+document.getElementById('btnUndo').addEventListener('click', function() {
+  if (!points.length) return;
+  points.pop();
+  const m = markers.pop();
+  if (m) map.removeLayer(m);
+  render();
+});
+
+document.getElementById('btnClear').addEventListener('click', function() {
+  points = [];
+  markers.forEach(m => map.removeLayer(m));
+  markers = [];
+  render();
+});
+
+document.getElementById('bufferKm').addEventListener('input', updateOutput);
+
+document.getElementById('btnCopy').addEventListener('click', function() {
+  if (points.length < 3) return;
+  const text = document.getElementById('output').textContent;
+  navigator.clipboard.writeText(text).then(() => {
+    const btn = document.getElementById('btnCopy');
+    btn.textContent = 'Copied!';
+    btn.classList.add('copied');
+    setTimeout(() => { btn.textContent = 'Copy'; btn.classList.remove('copied'); }, 2000);
+  });
+});
+</script>
+</body>
+</html>

public/hop-display.js

@@ -81,9 +81,13 @@ window.HopDisplay = (function() {
     const regionalConflicts = conflicts.filter(c => c.regional);
     const badgeCount = regionalConflicts.length > 0 ? regionalConflicts.length : (globalFallback ? conflicts.length : 0);
     const conflictData = escapeHtml(JSON.stringify({ h, conflicts, globalFallback }));
-    const warnBadge = badgeCount > 1
+    const conflictBadge = badgeCount > 1
       ? ` <button class="hop-conflict-btn" data-conflict='${conflictData}' onclick="event.preventDefault();event.stopPropagation();HopDisplay._showFromBtn(this)" title="${badgeCount} candidates — click for details">⚠${badgeCount}</button>`
       : '';
+    const unreliableBadge = unreliable
+      ? ' <button class="hop-unreliable-btn" aria-label="Unreliable name resolution" title="Unreliable name resolution — this hash\u2192name match is geographically inconsistent with the surrounding path hops. The repeater itself may be fine; this specific hop assignment is uncertain.">⚠️</button>'
+      : '';
+    const warnBadge = conflictBadge + unreliableBadge;
 
     const cls = [
       'hop',

public/index.html

@@ -95,6 +95,7 @@
   <script src="table-sort.js?v=__BUST__"></script>
   <script src="packet-filter.js?v=__BUST__"></script>
   <script src="packet-helpers.js?v=__BUST__"></script>
+  <script src="channel-decrypt.js?v=__BUST__"></script>
   <script src="channel-colors.js?v=__BUST__"></script>
   <script src="channel-color-picker.js?v=__BUST__"></script>
   <script src="packets.js?v=__BUST__"></script>

public/live.css

@@ -132,7 +132,7 @@
 
 /* ---- Node Detail Panel ---- */
 .live-node-detail {
-  top: 60px;
+  top: 64px;
   right: 12px;
   width: 320px;
   max-height: calc(100vh - 140px);
@@ -325,11 +325,14 @@
   }
   .live-stats-row { flex-wrap: wrap; gap: 4px; }
   .live-stat-pill { font-size: 11px; padding: 2px 7px; }
-  .live-toggles { font-size: 10px; gap: 6px; margin-left: 0; }
+  .live-toggles { font-size: 10px; gap: 6px; margin-left: 0; overflow-x: auto; flex-wrap: nowrap; -webkit-overflow-scrolling: touch; width: 100%; min-width: 0; }
   .live-title { font-size: 12px; letter-spacing: 1px; }
   /* #203 — bottom-sheet node detail on mobile */
-  .live-node-detail { width: 100%; right: 0; left: 0; top: auto; bottom: 0; max-height: 60vh; border-radius: 16px 16px 0 0; overflow-y: auto; }
+  .live-node-detail { width: 100%; right: 0; left: 0; top: auto; bottom: 0; max-height: 60dvh; border-radius: 16px 16px 0 0; overflow-y: auto; z-index: 1050; }
   .live-node-detail.hidden { transform: translateY(100%); }
+  /* Close button was unreachable: panel-header collapsed to 8px on mobile, panel-content
+     scroll area started at y=8, overlapping the button's 36px tap target (y=6–42) */
+  .live-node-detail .panel-header { min-height: 44px; }
   .feed-detail-card {
     position: fixed !important;
     right: 0 !important;
@@ -689,6 +692,18 @@
 .live-feed { bottom: 68px; }
 .feed-show-btn { bottom: 68px !important; }
 
+/* Backdrop for mobile tap-outside-to-close (#797) */
+.node-detail-backdrop {
+  display: none;
+  position: absolute;
+  inset: 0;
+  z-index: 1049;
+  background: rgba(0, 0, 0, 0.25);
+}
+@media (max-width: 640px) {
+  .node-detail-backdrop.active { display: block; }
+}
+
 /* Mobile VCR */
 @media (max-width: 640px) {
   /* Mobile VCR: two-row stacked layout */

public/live.js

@@ -849,6 +849,7 @@
           <div class="panel-content" aria-live="polite" aria-relevant="additions" role="log"></div>
         </div>
         <button class="feed-show-btn hidden" id="feedShowBtn" title="Show feed">📋</button>
+        <div id="nodeDetailBackdrop" class="node-detail-backdrop"></div>
         <div class="live-overlay live-node-detail hidden" id="liveNodeDetail">
           <div class="panel-header">
             <button class="panel-corner-btn" data-panel="liveNodeDetail" title="Move panel to next corner" aria-label="Move panel to next corner">◫</button>
@@ -1216,10 +1217,14 @@
     // Node detail panel
     const nodeDetailPanel = document.getElementById('liveNodeDetail');
     const nodeDetailContent = document.getElementById('nodeDetailContent');
-    document.getElementById('nodeDetailClose').addEventListener('click', () => {
+    const nodeDetailBackdrop = document.getElementById('nodeDetailBackdrop');
+    function closeNodeDetail() {
       activeNodeDetailKey = null;
       nodeDetailPanel.classList.add('hidden');
-    });
+      nodeDetailBackdrop.classList.remove('active');
+    }
+    document.getElementById('nodeDetailClose').addEventListener('click', closeNodeDetail);
+    nodeDetailBackdrop.addEventListener('click', closeNodeDetail);
 
     // Feed panel resize handle (#27)
     const savedFeedWidth = localStorage.getItem('live-feed-width');
@@ -1451,6 +1456,7 @@
     const panel = document.getElementById('liveNodeDetail');
     const content = document.getElementById('nodeDetailContent');
     panel.classList.remove('hidden');
+    document.getElementById('nodeDetailBackdrop').classList.add('active');
     content.innerHTML = '<div style="padding:20px;color:var(--text-muted)">Loading…</div>';
     try {
       const [data, healthData] = await Promise.all([
@@ -2730,6 +2736,7 @@
     const preview = text ? ' ' + (text.length > 35 ? text.slice(0, 35) + '…' : text) : '';
     const hopStr = hops.length ? `<span class="feed-hops">${hops.length}⇢</span>` : '';
     const obsBadge = pkt.observation_count > 1 ? `<span class="badge badge-obs" style="font-size:10px;margin-left:4px">👁 ${pkt.observation_count}</span>` : '';
+    const anomalyIcon = (pkt.decoded && pkt.decoded.anomaly) ? '<span title="Anomaly detected" style="margin-left:4px">⚠️</span>' : '';
     var _ccPayload2 = (pkt.decoded || {}).payload || {};
     var _ccChan = (typeName === 'GRP_TXT' || typeName === 'CHAN') ? (_ccPayload2.channel || null) : null;
     var dotHtml = _ccChan ? _feedColorDot(_ccChan) : '';
@@ -2744,7 +2751,7 @@
     item.innerHTML = `
       <span class="feed-icon" style="color:${color}">${icon}</span>
       <span class="feed-type" style="color:${color}">${typeName}</span>
-      ${dotHtml}${transportBadge(pkt.route_type)}${hopStr}${obsBadge}
+      ${dotHtml}${transportBadge(pkt.route_type)}${hopStr}${obsBadge}${anomalyIcon}
       <span class="feed-text">${escapeHtml(preview)}</span>
       <span class="feed-time" data-ts="${pkt._ts || Date.now()}">${formatLiveTimestampHtml(pkt._ts || Date.now())}</span>
     `;

public/map.js

@@ -25,7 +25,7 @@
 
   // Roles loaded from shared roles.js (ROLE_STYLE, ROLE_LABELS, ROLE_COLORS globals)
 
-  function makeMarkerIcon(role, isStale) {
+  function makeMarkerIcon(role, isStale, isAlsoObserver) {
     const s = ROLE_STYLE[role] || ROLE_STYLE.companion;
     const size = s.radius * 2 + 4;
     const c = size / 2;
@@ -56,7 +56,22 @@
       default: // circle
         path = `<circle cx="${c}" cy="${c}" r="${c-2}" fill="${s.color}" stroke="#fff" stroke-width="2"/>`;
     }
-    const svg = `<svg width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" xmlns="http://www.w3.org/2000/svg">${path}</svg>`;
+    // If this node is also an observer, add a small star overlay
+    let obsOverlay = '';
+    if (isAlsoObserver) {
+      const starSize = 8;
+      const sx = size - starSize, sy = 0;
+      const scx = starSize / 2, scy = starSize / 2, so = starSize / 2 - 0.5, si = so * 0.4;
+      let starPts = '';
+      for (let i = 0; i < 5; i++) {
+        const aO = (i * 72 - 90) * Math.PI / 180;
+        const aI = ((i * 72) + 36 - 90) * Math.PI / 180;
+        starPts += `${scx + so * Math.cos(aO)},${scy + so * Math.sin(aO)} `;
+        starPts += `${scx + si * Math.cos(aI)},${scy + si * Math.sin(aI)} `;
+      }
+      obsOverlay = `<g transform="translate(${sx},${sy})"><polygon points="${starPts.trim()}" fill="${ROLE_COLORS.observer || '#f1c40f'}" stroke="#fff" stroke-width="0.8"/></g>`;
+    }
+    const svg = `<svg width="${size}" height="${size}" viewBox="0 0 ${size} ${size}" xmlns="http://www.w3.org/2000/svg">${path}${obsOverlay}</svg>`;
     return L.divIcon({
       html: svg,
       className: 'meshcore-marker' + (isStale ? ' marker-stale' : ''),
@@ -66,14 +81,16 @@
     });
   }
 
-  function makeRepeaterLabelIcon(node, isStale) {
+  function makeRepeaterLabelIcon(node, isStale, isAlsoObserver) {
     var s = ROLE_STYLE['repeater'] || ROLE_STYLE.companion;
     var hs = node.hash_size || 1;
     // Show the short mesh hash ID (first N bytes of pubkey, uppercased)
     var shortHash = node.public_key ? node.public_key.slice(0, hs * 2).toUpperCase() : '??';
     var bgColor = s.color;
+    // If this repeater is also an observer, show a star indicator inside the label
+    var obsIndicator = isAlsoObserver ? ' <span style="color:' + (ROLE_COLORS.observer || '#f1c40f') + ';font-size:13px;line-height:1;" title="Also an observer">★</span>' : '';
     var html = '<div style="background:' + bgColor + ';color:#fff;font-weight:bold;font-size:11px;padding:2px 5px;border-radius:3px;border:2px solid #fff;box-shadow:0 1px 3px rgba(0,0,0,0.4);text-align:center;line-height:1.2;white-space:nowrap;">' +
-      shortHash + '</div>';
+      shortHash + obsIndicator + '</div>';
     return L.divIcon({
       html: html,
       className: 'meshcore-marker meshcore-label-marker' + (isStale ? ' marker-stale' : ''),
@@ -547,7 +564,8 @@
     const el = document.getElementById('mcRoleChecks');
     if (!el) return;
     el.innerHTML = '';
-    const obsCount = observers.filter(o => o.lat && o.lon).length;
+    const nodePubkeys = new Set(nodes.map(n => (n.public_key || '').toLowerCase()));
+    const obsCount = observers.filter(o => o.lat && o.lon && !(o.id && nodePubkeys.has(o.id.toLowerCase()))).length;
     const roles = ['repeater', 'companion', 'room', 'sensor', 'observer'];
     const shapeMap = { repeater: '◆', companion: '●', room: '■', sensor: '▲', observer: '★' };
 
@@ -638,6 +656,7 @@
   var _renderingMarkers = false;
   var _lastDeconflictZoom = null;
   var _currentMarkerData = []; // stored marker data for zoom-only repositioning
+  var _observerByPubkey = new Map(); // observer id (pubkey) → observer object, rebuilt on each render
   var _zoomResizeTimer = null;
 
   function deconflictLabels(markers, mapRef) {
@@ -780,19 +799,31 @@
 
     const allMarkers = [];
 
+    // Build a set of observer public keys for quick lookup
+    _observerByPubkey = new Map();
+    for (const obs of observers) {
+      if (obs.id) _observerByPubkey.set(obs.id.toLowerCase(), obs);
+    }
+
     for (const node of filtered) {
       const lastSeenTime = node.last_heard || node.last_seen;
       const isStale = getNodeStatus(node.role || 'companion', lastSeenTime ? new Date(lastSeenTime).getTime() : 0) === 'stale';
+      const pk = (node.public_key || '').toLowerCase();
+      const isAlsoObserver = _observerByPubkey.has(pk);
       const useLabel = node.role === 'repeater' && filters.hashLabels;
-      const icon = useLabel ? makeRepeaterLabelIcon(node, isStale) : makeMarkerIcon(node.role || 'companion', isStale);
+      const icon = useLabel ? makeRepeaterLabelIcon(node, isStale, isAlsoObserver) : makeMarkerIcon(node.role || 'companion', isStale, isAlsoObserver);
       const latLng = L.latLng(node.lat, node.lon);
-      allMarkers.push({ latLng, node, icon, isLabel: useLabel, popupFn: function() { return buildPopup(node); }, alt: (node.name || 'Unknown') + ' (' + (node.role || 'node') + ')' });
+      allMarkers.push({ latLng, node, icon, isLabel: useLabel, popupFn: function() { return buildPopup(node); }, alt: (node.name || 'Unknown') + ' (' + (node.role || 'node') + (isAlsoObserver ? ' + observer' : '') + ')' });
     }
 
-    // Add observer markers
+    // Add observer markers (skip observers already represented as a node marker)
+    // Build set of node pubkeys that are displayed on the map
+    const displayedNodePubkeys = new Set(filtered.map(n => (n.public_key || '').toLowerCase()));
     if (filters.observer) {
       for (const obs of observers) {
         if (!obs.lat || !obs.lon) continue;
+        // Skip observers whose pubkey matches a displayed node — they're shown as combined markers
+        if (obs.id && displayedNodePubkeys.has(obs.id.toLowerCase())) continue;
         const icon = makeMarkerIcon('observer');
         const latLng = L.latLng(obs.lat, obs.lon);
         allMarkers.push({ latLng, node: obs, icon, isLabel: false, popupFn: function() { return buildObserverPopup(obs); }, alt: (obs.name || obs.id || 'Unknown') + ' (observer)' });
@@ -909,6 +940,9 @@
     const loc = (node.lat && node.lon) ? `${node.lat.toFixed(5)}, ${node.lon.toFixed(5)}` : '—';
     const lastAdvert = node.last_seen ? timeAgo(node.last_seen) : '—';
     const roleBadge = `<span style="display:inline-block;padding:2px 8px;border-radius:12px;font-size:11px;font-weight:600;background:${ROLE_COLORS[node.role] || '#4b5563'};color:#fff;">${(node.role || 'unknown').toUpperCase()}</span>`;
+    // Check if this node is also an observer (combined repeater+observer)
+    const matchingObs = node.public_key ? _observerByPubkey.get(node.public_key.toLowerCase()) : null;
+    const obsBadge = matchingObs ? ` <span style="display:inline-block;padding:2px 8px;border-radius:12px;font-size:11px;font-weight:600;background:${ROLE_COLORS.observer || '#f1c40f'};color:#fff;">OBSERVER</span>` : '';
     const hs = node.hash_size || 1;
     const hashPrefix = node.public_key ? node.public_key.slice(0, hs * 2).toUpperCase() : '—';
     const hashPrefixRow = `<dt style="color:var(--text-muted);float:left;clear:left;width:80px;padding:2px 0;">Hash Prefix</dt>
@@ -917,7 +951,7 @@
     return `
       <div class="map-popup" style="font-family:var(--font);min-width:180px;">
         <h3 style="font-weight:700;font-size:14px;margin:0 0 4px;">${safeEsc(node.name || 'Unknown')}</h3>
-        ${roleBadge}
+        ${roleBadge}${obsBadge}
         <dl style="margin-top:8px;font-size:12px;">
           ${hashPrefixRow}
           <dt style="color:var(--text-muted);float:left;clear:left;width:80px;padding:2px 0;">Key</dt>
@@ -931,7 +965,7 @@
         </dl>
         <div style="margin-top:8px;clear:both;">
           <a href="#/nodes/${node.public_key}" style="color:var(--accent);font-size:12px;">View Node →</a>
-          ${node.public_key ? ` · <a href="#" data-show-neighbors data-pubkey="${escapeHtml(node.public_key)}" data-name="${escapeHtml(node.name || 'Unknown')}" style="color:var(--accent);font-size:12px;">Show Neighbors</a>` : ''}
+          ${node.public_key ? ` · <a href="javascript:void(0)" role="button" data-show-neighbors data-pubkey="${escapeHtml(node.public_key)}" data-name="${escapeHtml(node.name || 'Unknown')}" style="color:var(--accent);font-size:12px;cursor:pointer;">Show Neighbors</a>` : ''}
         </div>
       </div>`;
   }

public/nodes.js

@@ -286,11 +286,29 @@
       if (h) h.textContent = 'Neighbors (' + data.neighbors.length + ')';
     }
     var html = renderNeighborTable(data.neighbors, limit);
-    if (limit && data.neighbors.length > limit && viewAllPubkey) {
-      html += '<div style="margin-top:6px;text-align:right"><a href="#/nodes/' + encodeURIComponent(viewAllPubkey) + '?section=node-neighbors" style="font-size:12px">View all ' + data.neighbors.length + ' neighbors →</a></div>';
+    if (limit && data.neighbors.length > limit) {
+      html += '<div style="margin-top:6px;text-align:right"><button class="btn-link show-all-neighbors-btn" style="font-size:12px;cursor:pointer;background:none;border:none;color:var(--accent);padding:0">Show all ' + data.neighbors.length + ' neighbors ▼</button></div>';
+    } else if (!limit && data.neighbors.length > 5) {
+      // Collapse toggle when expanded (#855)
+      html += '<div style="margin-top:6px;text-align:right"><button class="btn-link collapse-neighbors-btn" style="font-size:12px;cursor:pointer;background:none;border:none;color:var(--accent);padding:0">Show fewer ▲</button></div>';
     }
     el.innerHTML = html;
 
+    // Wire "Show all neighbors" expand button (#855)
+    var expandBtn = el.querySelector('.show-all-neighbors-btn');
+    if (expandBtn) {
+      expandBtn.addEventListener('click', function() {
+        renderNeighborData(data, containerId, 0, headerSelector, null);
+      });
+    }
+    // Wire collapse button (#855)
+    var collapseBtn = el.querySelector('.collapse-neighbors-btn');
+    if (collapseBtn) {
+      collapseBtn.addEventListener('click', function() {
+        renderNeighborData(data, containerId, 5, headerSelector, null);
+      });
+    }
+
     // Initialize TableSort on neighbor table
     var neighborTable = el.querySelector('.neighbor-sort-table');
     if (neighborTable && window.TableSort) {
@@ -319,7 +337,10 @@
     directNode = routeParam || null;
 
     if (directNode) {
-      // Full-screen single node view
+      // Full-screen single node view (desktop + mobile).
+      // Reached via the 🔍 Details link or a deep link to #/nodes/{pubkey}.
+      // Row clicks use history.replaceState (no hashchange → no re-init),
+      // so the split-panel UX on desktop is preserved.
       app.innerHTML = `<div class="node-fullscreen">
         <div class="node-full-header">
           <button class="detail-back-btn node-back-btn" id="nodeBackBtn" aria-label="Back to nodes">←</button>
@@ -352,7 +373,7 @@
 
     app.innerHTML = `<div class="nodes-page">
       <div class="nodes-topbar">
-        <input type="text" class="nodes-search" id="nodeSearch" placeholder="Search nodes by name…" aria-label="Search nodes by name">
+        <input type="text" class="nodes-search" id="nodeSearch" placeholder="Search by name or pubkey prefix…" aria-label="Search nodes by name or pubkey prefix">
         <div class="nodes-counts" id="nodeCounts"></div>
       </div>
       <div id="nodesRegionFilter" class="region-filter-container"></div>
@@ -363,7 +384,7 @@
     </div>`;
 
     RegionFilter.init(document.getElementById('nodesRegionFilter'));
-    regionChangeHandler = RegionFilter.onChange(function () { _allNodes = null; loadNodes(); });
+    regionChangeHandler = RegionFilter.onChange(function () { _allNodes = null; _fleetSkew = null; loadNodes(); });
 
     if (search) {
       var _si = document.getElementById('nodeSearch');
@@ -377,6 +398,7 @@
     }, 250));
 
     loadNodes();
+    if (directNode) selectNode(directNode);
     // Auto-refresh when ADVERT packets arrive via WebSocket (fixes #131)
     wsHandler = debouncedOnWS(function (msgs) {
       const advertMsgs = msgs.filter(isAdvertMessage);
@@ -409,6 +431,7 @@
 
       if (needReload) {
         _allNodes = null;
+        _fleetSkew = null;
         invalidateApiCache('/nodes');
       }
       loadNodes(true);
@@ -493,6 +516,8 @@
           <tr><td>Hash Prefix</td><td>${n.hash_size ? '<code style="font-family:var(--mono);font-weight:700">' + n.public_key.slice(0, n.hash_size * 2).toUpperCase() + '</code> (' + n.hash_size + '-byte)' : 'Unknown'}${n.hash_size_inconsistent ? ' <span style="color:var(--status-yellow);cursor:help" title="Seen: ' + (Array.isArray(n.hash_sizes_seen) ? n.hash_sizes_seen : []).join(', ') + '-byte">⚠️ varies</span>' : ''}</td></tr>
         </table>
 
+        <div class="node-full-card skew-detail-section" id="node-clock-skew" style="display:none"></div>
+
         ${observers.length ? `<div class="node-full-card" id="node-observers">
           ${(() => { const regions = [...new Set(observers.map(o => o.iata).filter(Boolean))]; return regions.length ? `<div style="margin-bottom:8px"><strong>Regions:</strong> ${regions.map(r => '<span class="badge" style="margin:0 2px">' + escapeHtml(r) + '</span>').join(' ')}</div>` : ''; })()}
           <h4>Heard By (${observers.length} observer${observers.length > 1 ? 's' : ''})</h4>
@@ -534,9 +559,10 @@
         </div>
 
         <div class="node-full-card" id="node-packets">
-          <h4>Recent Packets (${adverts.length})</h4>
+          ${(() => { const validPackets = adverts.filter(p => p.hash && p.timestamp); return `
+          <h4>Recent Packets (${validPackets.length})</h4>
           <div class="node-activity-list">
-            ${adverts.length ? adverts.map(p => {
+            ${validPackets.length ? validPackets.map(p => {
               let decoded; try { decoded = JSON.parse(p.decoded_json); } catch {}
               const typeLabel = p.payload_type === 4 ? '📡 Advert' : p.payload_type === 5 ? '💬 Channel' : p.payload_type === 2 ? '✉️ DM' : '📦 Packet';
               const detail = decoded?.text ? ': ' + escapeHtml(truncate(decoded.text, 50)) : decoded?.name ? ' — ' + escapeHtml(decoded.name) : '';
@@ -562,6 +588,7 @@
               </div>`;
             }).join('') : '<div class="text-muted">No recent packets</div>'}
           </div>
+        `; })()}
         </div>`;
 
       // Map
@@ -624,6 +651,10 @@
         headerSelector: '#fullNeighborsHeader'
       });
 
+      // #690 — Clock Skew detail section (full-screen view)
+      loadClockSkewInto(document.getElementById('node-clock-skew'), n.public_key);
+
+
       // Affinity debug panel — show if debugAffinity is enabled
       (function loadAffinityDebug() {
         var show = (window.CLIENT_CONFIG && window.CLIENT_CONFIG.debugAffinity) || localStorage.getItem('meshcore-affinity-debug') === 'true';
@@ -777,6 +808,59 @@
   let _themeRefreshHandler = null;
 
   let _allNodes = null; // cached full node list
+  let _fleetSkew = null; // cached clock skew map: pubkey → {severity, recentMedianSkewSec, medianSkewSec, ...}
+
+  /**
+   * Fetch per-node clock skew and render into the given container element.
+   * Shared between the full-screen detail page and the side panel (#813, #690).
+   * No-op if the container is missing, the API errors, or the response lacks severity.
+   */
+  async function loadClockSkewInto(container, pubkey) {
+    if (!container) return;
+    try {
+      var cs = await api('/nodes/' + encodeURIComponent(pubkey) + '/clock-skew', { ttl: 30000 });
+      if (!cs || !cs.severity) return;
+      container.style.display = '';
+      var driftHtml = cs.driftPerDaySec ? '<div style="font-size:12px;color:var(--text-muted);margin-top:2px">Drift: ' + formatDrift(cs.driftPerDaySec) + '</div>' : '';
+      var sparkHtml = renderSkewSparkline(cs.samples, 200, 32);
+      var skewVal = window.currentSkewValue(cs);
+      var skewDisplay = cs.severity === 'no_clock'
+        ? '<span style="font-size:18px;font-weight:700;color:var(--text-muted)">No Clock</span>'
+        : '<span style="font-size:18px;font-weight:700;font-family:var(--mono)">' + formatSkew(skewVal) + '</span>';
+      var bimodalWarning = '';
+      if (cs.severity === 'bimodal_clock') {
+        var totalRecent = cs.recentSampleCount || 0;
+        bimodalWarning = '<div style="font-size:12px;color:var(--status-amber-text);margin-top:4px">⚠️ ' + (cs.recentBadSampleCount || '?') + ' of last ' + (totalRecent || '?') + ' adverts had nonsense timestamps (likely RTC reset)</div>';
+      }
+      container.innerHTML =
+        '<h4 style="margin:0 0 6px">⏰ Clock Skew</h4>' +
+        '<div style="display:flex;align-items:center;gap:12px;flex-wrap:wrap">' +
+          skewDisplay +
+          renderSkewBadge(cs.severity, skewVal, cs) +
+          (cs.calibrated ? ' <span style="font-size:10px;color:var(--text-muted)" title="Observer-calibrated">✓ calibrated</span>' : '') +
+        '</div>' +
+        driftHtml +
+        (sparkHtml ? '<div class="skew-sparkline-wrap" style="margin-top:8px">' + sparkHtml + '<div style="font-size:10px;color:var(--text-muted)">Skew over time (' + (cs.samples || []).length + ' samples)</div></div>' : '') +
+        bimodalWarning;
+    } catch (e) {
+      // Non-fatal — section stays hidden
+    }
+  }
+
+  /** Fetch fleet clock skew once, return map keyed by pubkey */
+  async function getFleetSkew() {
+    if (_fleetSkew) return _fleetSkew;
+    try {
+      const data = await api('/nodes/clock-skew', { ttl: 30000 });
+      _fleetSkew = {};
+      (Array.isArray(data) ? data : []).forEach(function(cs) {
+        if (cs && cs.pubkey) _fleetSkew[cs.pubkey] = cs;
+      });
+    } catch (e) {
+      _fleetSkew = {};
+    }
+    return _fleetSkew;
+  }
 
   // Build a map of lowercased name → count of distinct pubkeys sharing that name
   function buildDupNameMap(allNodes) {
@@ -806,7 +890,10 @@
         const params = new URLSearchParams({ limit: '5000' });
         const rp = RegionFilter.getRegionParam();
         if (rp) params.set('region', rp);
-        const data = await api('/nodes?' + params, { ttl: CLIENT_TTL.nodeList });
+        const [data] = await Promise.all([
+          api('/nodes?' + params, { ttl: CLIENT_TTL.nodeList }),
+          getFleetSkew() // pre-fetch clock skew in parallel
+        ]);
         _allNodes = data.nodes || [];
         counts = data.counts || {};
       }
@@ -815,8 +902,7 @@
       let filtered = _allNodes;
       if (activeTab !== 'all') filtered = filtered.filter(n => (n.role || '').toLowerCase() === activeTab);
       if (search) {
-        const q = search.toLowerCase();
-        filtered = filtered.filter(n => (n.name || '').toLowerCase().includes(q) || (n.public_key || '').toLowerCase().includes(q));
+        filtered = filtered.filter(n => window._nodesMatchesSearch(n, search));
       }
       if (lastHeard) {
         const ms = { '1h': 3600000, '2h': 7200000, '6h': 21600000, '12h': 43200000, '24h': 86400000, '48h': 172800000, '3d': 259200000, '7d': 604800000, '14d': 1209600000, '30d': 2592000000 }[lastHeard];
@@ -979,6 +1065,7 @@
           panel.classList.add('empty');
           panel.innerHTML = '<span>Select a node to view details</span>';
           selectedKey = null;
+          history.replaceState(null, '', '#/nodes');
           renderRows();
         }
       }
@@ -986,11 +1073,25 @@
 
     // #630: Close button for node detail panel (important for mobile full-screen overlay)
     document.getElementById('nodesRight').addEventListener('click', function(e) {
+      // #778/#856: Analytics link — force hashchange via replaceState + assign.
+      // (Details button is handled separately via .node-detail-btn click listener)
+      var link = e.target.closest('a.btn-primary[href^="#/nodes/"]');
+      if (link) {
+        e.preventDefault();
+        var href = link.getAttribute('href');
+        if (href.indexOf('/analytics') !== -1) {
+          // Analytics link — different page, force hashchange via replaceState + assign
+          history.replaceState(null, '', '#/');
+          location.hash = href.substring(1);
+        }
+        return;
+      }
       if (e.target.closest('.panel-close-btn')) {
         const panel = document.getElementById('nodesRight');
         panel.classList.add('empty');
         panel.innerHTML = '<span>Select a node to view details</span>';
         selectedKey = null;
+        history.replaceState(null, '', '#/nodes');
         renderRows();
       }
     });
@@ -1029,8 +1130,10 @@
       const lastSeenTime = n.last_heard || n.last_seen;
       const status = getNodeStatus(n.role || 'companion', lastSeenTime ? new Date(lastSeenTime).getTime() : 0);
       const lastSeenClass = status === 'active' ? 'last-seen-active' : 'last-seen-stale';
+      const cs = _fleetSkew && _fleetSkew[n.public_key];
+      const skewBadgeHtml = cs && cs.severity && cs.severity !== 'ok' ? renderSkewBadge(cs.severity, window.currentSkewValue(cs), cs) : '';
       return `<tr data-key="${n.public_key}" data-action="select" data-value="${n.public_key}" tabindex="0" role="row" class="${selectedKey === n.public_key ? 'selected' : ''}${isClaimed ? ' claimed-row' : ''}">
-        <td>${favStar(n.public_key, 'node-fav')}${isClaimed ? '<span class="claimed-badge" title="My Mesh">★</span> ' : ''}<strong>${n.name || '(unnamed)'}</strong>${dupNameBadge(n.name, n.public_key, dupMap)}</td>
+        <td>${favStar(n.public_key, 'node-fav')}${isClaimed ? '<span class="claimed-badge" title="My Mesh">★</span> ' : ''}<strong>${n.name || '(unnamed)'}</strong>${dupNameBadge(n.name, n.public_key, dupMap)}${skewBadgeHtml}</td>
         <td class="mono col-pubkey">${truncate(n.public_key, 16)}</td>
         <td><span class="badge" style="background:${roleColor}20;color:${roleColor}">${n.role}</span></td>
         <td class="${lastSeenClass}">${renderNodeTimestampHtml(n.last_heard || n.last_seen)}</td>
@@ -1048,6 +1151,7 @@
       return;
     }
     selectedKey = pubkey;
+    history.replaceState(null, '', '#/nodes/' + encodeURIComponent(pubkey));
     renderRows();
     const panel = document.getElementById('nodesRight');
     panel.classList.remove('empty');
@@ -1086,7 +1190,7 @@
       <div class="node-detail">
         <div class="node-detail-name">${escapeHtml(n.name || '(unnamed)')}${dupBadge}</div>
         <div class="node-detail-role">${renderNodeBadges(n, roleColor)}
-          <a href="#/nodes/${encodeURIComponent(n.public_key)}" class="btn-primary" style="display:inline-block;text-decoration:none;font-size:11px;padding:2px 8px;margin-left:8px">🔍 Details</a>
+          <button class="btn-primary node-detail-btn" data-pubkey="${encodeURIComponent(n.public_key)}" aria-label="View details for ${escapeHtml(n.name || n.public_key)}" style="font-size:11px;padding:2px 8px;margin-left:8px;cursor:pointer">🔍 Details</button>
           <a href="#/nodes/${encodeURIComponent(n.public_key)}/analytics" class="btn-primary" style="display:inline-block;margin-left:4px;text-decoration:none;font-size:11px;padding:2px 8px">📊 Analytics</a>
         </div>
         ${renderStatusExplanation(n)}
@@ -1113,6 +1217,8 @@
           </dl>
         </div>
 
+        <div class="node-detail-section skew-detail-section" id="node-clock-skew" style="display:none"></div>
+
         ${observers.length ? `<div class="node-detail-section">
           ${(() => { const regions = [...new Set(observers.map(o => o.iata).filter(Boolean))]; return regions.length ? `<div style="margin-bottom:6px;font-size:12px"><strong>Regions:</strong> ${regions.join(', ')}</div>` : ''; })()}
           <h4>Heard By (${observers.length} observer${observers.length > 1 ? 's' : ''})</h4>
@@ -1135,9 +1241,10 @@
         </div>
 
         <div class="node-detail-section">
-          <h4>Recent Packets (${adverts.length})</h4>
+          ${(() => { const validPackets = adverts.filter(a => a.hash && a.timestamp); return `
+          <h4>Recent Packets (${validPackets.length})</h4>
           <div id="advertTimeline">
-            ${adverts.length ? adverts.map(a => {
+            ${validPackets.length ? validPackets.map(a => {
               let decoded;
               try { decoded = JSON.parse(a.decoded_json); } catch {}
               const pType = PAYLOAD_TYPES[a.payload_type] || 'Packet';
@@ -1156,6 +1263,7 @@
               </div>`;
             }).join('') : '<div class="text-muted" style="padding:8px">No recent packets</div>'}
           </div>
+          `; })()}
         </div>
       </div>`;
 
@@ -1199,6 +1307,15 @@
       } catch {}
     }
 
+    // #856: Wire "Details" button to navigate to full-screen node view
+    var detailBtn = panel.querySelector('.node-detail-btn');
+    if (detailBtn) {
+      detailBtn.addEventListener('click', function() {
+        var pk = detailBtn.getAttribute('data-pubkey');
+        location.hash = '#/nodes/' + pk;
+      });
+    }
+
     // Fetch neighbors for this node (condensed panel — top 5)
     fetchAndRenderNeighbors(n.public_key, 'panelNeighborsContent', {
       limit: 5,
@@ -1206,6 +1323,10 @@
       viewAllPubkey: n.public_key
     });
 
+    // #813 — Clock Skew section in side panel (mirrors full-screen view)
+    loadClockSkewInto(document.getElementById('node-clock-skew'), n.public_key);
+
+
     // Fetch paths through this node
     api('/nodes/' + encodeURIComponent(n.public_key) + '/paths', { ttl: CLIENT_TTL.nodeDetail }).then(pathData => {
       const el = document.getElementById('pathsContent');
@@ -1304,4 +1425,14 @@
   window._nodesRenderNodeTimestampText = renderNodeTimestampText;
   window._nodesGetStatusInfo = getStatusInfo;
   window._nodesGetStatusTooltip = getStatusTooltip;
+
+  // #862: Expose search filter logic for testing
+  window._nodesMatchesSearch = function(node, query) {
+    if (!query) return true;
+    var q = query.toLowerCase();
+    var isHex = /^[0-9a-f]+$/i.test(q);
+    if ((node.name || '').toLowerCase().includes(q)) return true;
+    if (isHex && (node.public_key || '').toLowerCase().startsWith(q)) return true;
+    return false;
+  };
 })();

public/packets.js

@@ -45,6 +45,11 @@
     var parts = [];
     if (timeWindowMin && timeWindowMin !== DEFAULT_TIME_WINDOW) parts.push('timeWindow=' + timeWindowMin);
     if (regionParam) parts.push('region=' + encodeURIComponent(regionParam));
+    if (filters.hash) parts.push('hash=' + encodeURIComponent(filters.hash));
+    if (filters.node) parts.push('node=' + encodeURIComponent(filters.node));
+    if (filters.observer) parts.push('observer=' + encodeURIComponent(filters.observer));
+    if (filters.channel) parts.push('channel=' + encodeURIComponent(filters.channel));
+    if (filters._filterExpr) parts.push('filter=' + encodeURIComponent(filters._filterExpr));
     return parts.length ? '?' + parts.join('&') : '';
   }
   window.buildPacketsQuery = buildPacketsQuery;
@@ -342,6 +347,16 @@
     }
     var _urlRegion = _initUrlParams.get('region');
     if (_urlRegion) _pendingUrlRegion = _urlRegion;
+    var _urlHash = _initUrlParams.get('hash');
+    if (_urlHash) filters.hash = _urlHash;
+    var _urlNode = _initUrlParams.get('node');
+    if (_urlNode) { filters.node = _urlNode; filters.nodeName = _urlNode.slice(0, 8); }
+    var _urlObserver = _initUrlParams.get('observer');
+    if (_urlObserver) filters.observer = _urlObserver;
+    var _urlChannel = _initUrlParams.get('channel');
+    if (_urlChannel) filters.channel = _urlChannel;
+    var _urlFilterExpr = _initUrlParams.get('filter');
+    if (_urlFilterExpr) filters._filterExpr = _urlFilterExpr;
 
     app.innerHTML = `<div class="split-layout detail-collapsed">
       <div class="panel-left" id="pktLeft" aria-live="polite" aria-relevant="additions removals"></div>
@@ -372,7 +387,7 @@
             const obs = data.observations.find(o => String(o.id) === String(obsTarget));
             if (obs) {
               expandedHashes.add(h);
-              const obsPacket = {...data.packet, observer_id: obs.observer_id, observer_name: obs.observer_name, snr: obs.snr, rssi: obs.rssi, path_json: obs.path_json, resolved_path: obs.resolved_path, timestamp: obs.timestamp, first_seen: obs.timestamp};
+              const obsPacket = {...data.packet, observer_id: obs.observer_id, observer_name: obs.observer_name, snr: obs.snr, rssi: obs.rssi, path_json: obs.path_json, resolved_path: obs.resolved_path, direction: obs.direction, timestamp: obs.timestamp, first_seen: obs.timestamp};
               clearParsedCache(obsPacket);
               selectPacket(obs.id, h, {packet: obsPacket, breakdown: data.breakdown, observations: data.observations}, obs.id);
             } else {
@@ -610,6 +625,7 @@
       if (filters.hash) params.set('hash', filters.hash);
       if (filters.node) params.set('node', filters.node);
       if (filters.observer) params.set('observer', filters.observer);
+      if (filters.channel) params.set('channel', filters.channel);
       if (groupByHash) {
         params.set('groupByHash', 'true');
       } else {
@@ -738,6 +754,11 @@
             <button class="multi-select-trigger" id="typeTrigger" title="Filter by packet type">All Types ▾</button>
             <div class="multi-select-menu" id="typeMenu"></div>
           </div>
+          <div class="filter-group" style="display:inline-flex;align-items:center;gap:4px">
+            <select id="fChannel" class="filter-select" aria-label="Filter by channel" title="Filter Channel Messages (GRP_TXT) by channel">
+              <option value="">All Channels</option>
+            </select>
+          </div>
         </div>
         <div class="filter-group">
           <button class="btn ${groupByHash ? 'active' : ''}" id="fGroup" title="Collapse duplicate observations of the same packet into expandable groups">Group by Hash</button>
@@ -797,6 +818,12 @@
       var pfError = document.getElementById('packetFilterError');
       var pfCount = document.getElementById('packetFilterCount');
       if (!pfInput || !window.PacketFilter) return;
+      // Restore Wireshark filter expression from URL
+      if (filters._filterExpr) {
+        pfInput.value = filters._filterExpr;
+        var _restored = PacketFilter.compile(filters._filterExpr);
+        if (!_restored.error) { pfInput.classList.add('filter-active'); filters._packetFilter = _restored.filter; }
+      }
       var pfTimer = null;
       pfInput.addEventListener('input', function() {
         clearTimeout(pfTimer);
@@ -807,6 +834,8 @@
             pfError.style.display = 'none';
             pfCount.style.display = 'none';
             filters._packetFilter = null;
+            filters._filterExpr = undefined;
+            updatePacketsUrl();
             renderTableRows();
             return;
           }
@@ -818,12 +847,16 @@
             pfError.style.display = 'block';
             pfCount.style.display = 'none';
             filters._packetFilter = null;
+            filters._filterExpr = undefined;
+            updatePacketsUrl();
             renderTableRows();
           } else {
             pfInput.classList.remove('filter-error');
             pfInput.classList.add('filter-active');
             pfError.style.display = 'none';
             filters._packetFilter = compiled.filter;
+            filters._filterExpr = expr;
+            updatePacketsUrl();
             renderTableRows();
           }
         }, 300);
@@ -868,6 +901,7 @@
       if (filters.observer) localStorage.setItem('meshcore-observer-filter', filters.observer); else localStorage.removeItem('meshcore-observer-filter');
       buildObserverMenu();
       updateObsTrigger();
+      updatePacketsUrl();
       renderTableRows();
     });
 
@@ -913,6 +947,63 @@
       renderTableRows();
     });
 
+    // --- Channel filter (#812) ---
+    // Server-side filter: /api/packets?channel=<hash>. Triggers loadPackets()
+    // (not just renderTableRows) so the filter applies before pagination.
+    const channelSel = document.getElementById('fChannel');
+    if (channelSel) {
+      if (filters.channel) {
+        // Pre-seed an option so the current filter shows as selected even
+        // before the channels list arrives. Replaced when populateChannels resolves.
+        const opt = document.createElement('option');
+        opt.value = filters.channel;
+        opt.textContent = filters.channel;
+        opt.selected = true;
+        channelSel.appendChild(opt);
+      }
+      api('/channels').then(data => {
+        const channels = (data && data.channels) || [];
+        // Build options via DOM API: channel names are network-supplied
+        // and must NOT be interpolated into innerHTML (XSS, #812).
+        // Sort alphabetically (case-insensitive) for predictable picker order;
+        // the API returns last-activity order which is unstable for a dropdown.
+        const sorted = channels.slice().sort((a, b) => {
+          const an = (a.name || a.hash || '').toLowerCase();
+          const bn = (b.name || b.hash || '').toLowerCase();
+          return an < bn ? -1 : an > bn ? 1 : 0;
+        });
+        channelSel.textContent = '';
+        const allOpt = document.createElement('option');
+        allOpt.value = '';
+        allOpt.textContent = 'All Channels';
+        channelSel.appendChild(allOpt);
+        let matched = false;
+        for (const ch of sorted) {
+          const v = ch.hash || ch.name || '';
+          if (!v) continue;
+          const opt = document.createElement('option');
+          opt.value = v;
+          opt.textContent = ch.name || v;
+          if (v === filters.channel) { opt.selected = true; matched = true; }
+          channelSel.appendChild(opt);
+        }
+        // If current filter isn't in the list (encrypted hash, stale, or
+        // race with cache), keep it as a selected option so the UI reflects state.
+        if (filters.channel && !matched) {
+          const opt = document.createElement('option');
+          opt.value = filters.channel;
+          opt.textContent = filters.channel;
+          opt.selected = true;
+          channelSel.appendChild(opt);
+        }
+      }).catch(() => {});
+      channelSel.addEventListener('change', (e) => {
+        filters.channel = e.target.value || undefined;
+        updatePacketsUrl();
+        loadPackets();
+      });
+    }
+
     // Close multi-select menus on outside click
     bindDocumentHandler('menu', 'click', (e) => {
       const obsWrap = document.getElementById('observerFilterWrap');
@@ -930,7 +1021,7 @@
 
     // Filter event listeners
     document.getElementById('fHash').value = filters.hash || '';
-    document.getElementById('fHash').addEventListener('input', debounce((e) => { filters.hash = e.target.value || undefined; loadPackets(); }, 300));
+    document.getElementById('fHash').addEventListener('input', debounce((e) => { filters.hash = e.target.value || undefined; updatePacketsUrl(); loadPackets(); }, 300));
 
     // Time window dropdown — restore from localStorage and bind change
     const fTimeWindow = document.getElementById('fTimeWindow');
@@ -1065,7 +1156,7 @@
       if (!q) {
         fNodeDrop.classList.add('hidden');
         fNode.setAttribute('aria-expanded', 'false');
-        if (filters.node) { filters.node = undefined; filters.nodeName = undefined; loadPackets(); }
+        if (filters.node) { filters.node = undefined; filters.nodeName = undefined; updatePacketsUrl(); loadPackets(); }
         return;
       }
       try {
@@ -1074,7 +1165,7 @@
         const nodes = data.nodes || [];
         if (nodes.length === 0) { fNodeDrop.classList.add('hidden'); fNode.setAttribute('aria-expanded', 'false'); return; }
         fNodeDrop.innerHTML = nodes.map((n, i) =>
-          `<div class="node-filter-option" id="fNodeOpt-${i}" role="option" data-key="${n.public_key}" data-name="${escapeHtml(n.name || n.public_key.slice(0,8))}">${escapeHtml(n.name || n.public_key.slice(0,8))} <span style="color:var(--muted);font-size:0.8em">${n.public_key.slice(0,8)}</span></div>`
+          `<div class="node-filter-option" id="fNodeOpt-${i}" role="option" data-key="${n.public_key}" data-name="${escapeHtml(n.name || n.public_key.slice(0,8))}">${escapeHtml(n.name || n.public_key.slice(0,8))} <span style="color:var(--text-muted);font-size:0.8em">${n.public_key.slice(0,8)}</span></div>`
         ).join('');
         fNodeDrop.classList.remove('hidden');
         fNode.setAttribute('aria-expanded', 'true');
@@ -1094,6 +1185,7 @@
       fNode.setAttribute('aria-expanded', 'false');
       fNode.setAttribute('aria-activedescendant', '');
       nodeActiveIdx = -1;
+      updatePacketsUrl();
       loadPackets();
     }
 
@@ -1154,7 +1246,7 @@
           const child = group?._children?.find(c => String(c.id) === String(value));
           if (child) {
             const parentData = group._fetchedData;
-            const obsPacket = parentData ? {...parentData.packet, observer_id: child.observer_id, observer_name: child.observer_name, snr: child.snr, rssi: child.rssi, path_json: child.path_json, resolved_path: child.resolved_path, timestamp: child.timestamp, first_seen: child.timestamp} : child;
+            const obsPacket = parentData ? {...parentData.packet, observer_id: child.observer_id, observer_name: child.observer_name, snr: child.snr, rssi: child.rssi, path_json: child.path_json, resolved_path: child.resolved_path, direction: child.direction, timestamp: child.timestamp, first_seen: child.timestamp} : child;
             if (parentData) { clearParsedCache(obsPacket); }
             selectPacket(child.id, parentHash, {packet: obsPacket, breakdown: parentData?.breakdown, observations: parentData?.observations}, child.id);
           }
@@ -1705,19 +1797,49 @@
       panel.innerHTML = isMobileNow ? '' : '<div class="panel-resize-handle" id="pktResizeHandle"></div>' + PANEL_CLOSE_HTML;
       const content = document.createElement('div');
       panel.appendChild(content);
-      await renderDetail(content, data);
+      await renderDetail(content, data, selectedObservationId);
       if (!isMobileNow) initPanelResize();
     } catch (e) {
       panel.innerHTML = `<div class="text-muted">Error: ${e.message}</div>`;
     }
   }
 
-  async function renderDetail(panel, data) {
+  async function renderDetail(panel, data, chosenObsId) {
     const pkt = data.packet;
     const breakdown = data.breakdown || {};
     const ranges = breakdown.ranges || [];
-    const decoded = getParsedDecoded(pkt) || {};
-    const pathHops = getParsedPath(pkt) || [];
+    const observations = data.observations || [];
+
+    // Per-observation rendering (issue #849):
+    // When opened from a packet row (no specific observer), default to first observation.
+    // When opened from an observation child row, use that observation.
+    // Clicking a different observation row in the detail re-renders with that observation.
+    let currentObs = null;
+    const targetObsId = chosenObsId || selectedObservationId;
+    if (targetObsId && observations.length) {
+      currentObs = observations.find(o => String(o.id) === String(targetObsId));
+    }
+    if (!currentObs && observations.length) {
+      currentObs = observations[0]; // fall back to first observation
+    }
+
+    // If we have a current observation, build pkt fields from it so summary is per-observation
+    const effectivePkt = currentObs ? clearParsedCache({...pkt, ...currentObs, _isObservation: true}) : pkt;
+    const decoded = getParsedDecoded(effectivePkt) || {};
+    const pathHops = getParsedPath(effectivePkt) || [];
+
+    // Cross-check: hop count from raw_hex path_len byte vs path_json length
+    const obsRawHex = effectivePkt.raw_hex || pkt.raw_hex || '';
+    let rawHopCount = null;
+    if (obsRawHex.length >= 4) {
+      // path_len byte position depends on route type
+      const plOff = getPathLenOffset(pkt.route_type);
+      const plByte = parseInt(obsRawHex.slice(plOff * 2, plOff * 2 + 2), 16);
+      if (!isNaN(plByte)) rawHopCount = plByte & 0x3F;
+    }
+    if (rawHopCount != null && pathHops.length !== rawHopCount) {
+      console.warn(`[CoreScope] Hop count inconsistency for packet ${pkt.hash}: path_json has ${pathHops.length} hops but raw_hex path_len has ${rawHopCount}. Trusting raw_hex.`);
+    }
 
     // Resolve sender GPS — from packet directly, or from known node in DB
     let senderLat = decoded.lat != null ? decoded.lat : (decoded.latitude || null);
@@ -1761,15 +1883,16 @@
     }
 
     // Parse hash size from path byte
-    const rawPathByte = pkt.raw_hex ? parseInt(pkt.raw_hex.slice(2, 4), 16) : NaN;
+    const plOff = getPathLenOffset(pkt.route_type);
+    const rawPathByte = pkt.raw_hex ? parseInt(pkt.raw_hex.slice(plOff * 2, plOff * 2 + 2), 16) : NaN;
     const hashSize = (isNaN(rawPathByte) || (rawPathByte & 0x3F) === 0) ? null : ((rawPathByte >> 6) + 1);
 
-    const size = pkt.raw_hex ? Math.floor(pkt.raw_hex.length / 2) : 0;
+    const size = effectivePkt.raw_hex ? Math.floor(effectivePkt.raw_hex.length / 2) : (pkt.raw_hex ? Math.floor(pkt.raw_hex.length / 2) : 0);
     const typeName = payloadTypeName(pkt.payload_type);
 
-    const snr = pkt.snr ?? decoded.SNR ?? decoded.snr ?? null;
-    const rssi = pkt.rssi ?? decoded.RSSI ?? decoded.rssi ?? null;
-    const hasRawHex = !!pkt.raw_hex;
+    const snr = effectivePkt.snr ?? decoded.SNR ?? decoded.snr ?? null;
+    const rssi = effectivePkt.rssi ?? decoded.RSSI ?? decoded.rssi ?? null;
+    const hasRawHex = !!(effectivePkt.raw_hex || pkt.raw_hex);
 
     // Build message preview
     let messageHtml = '';
@@ -1780,17 +1903,16 @@
       const meta = [chLabel, hopLabel, snrLabel].filter(Boolean).join(' · ');
       messageHtml = `<div class="detail-message" style="padding:12px;margin:8px 0;background:var(--card-bg);border-radius:8px;border-left:3px solid var(--accent)">
         <div style="font-size:1.1em">${escapeHtml(decoded.text)}</div>
-        ${meta ? `<div style="font-size:0.85em;color:var(--muted);margin-top:4px">${meta}</div>` : ''}
+        ${meta ? `<div style="font-size:0.85em;color:var(--text-muted);margin-top:4px">${meta}</div>` : ''}
       </div>`;
     } else if (decoded.type === 'GRP_TXT' && decoded.channelHash != null) {
       const hashHex = decoded.channelHashHex || decoded.channelHash.toString(16).padStart(2, '0').toUpperCase();
       const statusLabel = decoded.decryptionStatus === 'no_key' ? 'no key' : 'decryption failed';
       messageHtml = `<div class="detail-message" style="padding:12px;margin:8px 0;background:var(--card-bg);border-radius:8px;border-left:3px solid var(--warning, #f0ad4e)">
-        <div style="font-size:1.1em">🔒 Channel Hash: 0x${hashHex} <span style="color:var(--muted)">(${statusLabel})</span></div>
+        <div style="font-size:1.1em">🔒 Channel Hash: 0x${hashHex} <span style="color:var(--text-muted)">(${statusLabel})</span></div>
       </div>`;
     }
 
-    const observations = data.observations || [];
     const obsCount = data.observation_count || observations.length || 1;
     const uniqueObservers = new Set(observations.map(o => o.observer_id)).size;
 
@@ -1849,20 +1971,32 @@
       }
     }
 
+    const anomalyBanner = decoded.anomaly
+      ? `<div class="anomaly-banner" style="background:var(--warning, #f0ad4e); color:#000; padding:8px 12px; border-radius:4px; margin-bottom:8px; font-weight:600;">⚠️ Anomaly: ${escapeHtml(decoded.anomaly)}</div>`
+      : '';
+
+    // Hop count display: trust raw_hex (firmware truth) over path_json
+    const displayHopCount = rawHopCount != null ? rawHopCount : pathHops.length;
+    const obsIndicator = currentObs && observations.length > 1
+      ? `<span style="font-size:0.8em;color:var(--text-muted);margin-left:6px">(observation ${observations.indexOf(currentObs) + 1} of ${observations.length})</span>`
+      : '';
+
     panel.innerHTML = `
+      ${anomalyBanner}
       <div class="detail-title">${hasRawHex ? `Packet Byte Breakdown (${size} bytes)` : typeName + ' Packet'}</div>
-      <div class="detail-hash">${pkt.hash || 'Packet #' + pkt.id}</div>
+      <div class="detail-hash">${pkt.hash || 'Packet #' + pkt.id}${obsIndicator}</div>
       ${messageHtml}
       <dl class="detail-meta">
-        <dt>Observer</dt><dd>${obsName(pkt.observer_id)}</dd>
+        <dt>Observer</dt><dd>${obsName(effectivePkt.observer_id)}</dd>
         <dt>Location</dt><dd>${locationHtml}</dd>
         <dt>SNR / RSSI</dt><dd>${snr != null ? snr + ' dB' : '—'} / ${rssi != null ? rssi + ' dBm' : '—'}</dd>
         <dt>Route Type</dt><dd>${routeTypeName(pkt.route_type)}</dd>
         <dt>Payload Type</dt><dd><span class="badge badge-${payloadTypeColor(pkt.payload_type)}">${typeName}</span></dd>
         ${hashSize ? `<dt>Hash Size</dt><dd>${hashSize} byte${hashSize !== 1 ? 's' : ''}</dd>` : ''}
-        <dt>Timestamp</dt><dd>${renderTimestampCell(pkt.timestamp)}</dd>
+        <dt>Timestamp</dt><dd>${renderTimestampCell(effectivePkt.timestamp)}</dd>
         <dt>Propagation</dt><dd>${propagationHtml}</dd>
-        <dt>Path</dt><dd>${pathHops.length ? renderPath(pathHops, pkt.observer_id) : '—'}</dd>
+        <dt>Path</dt><dd>${displayHopCount > 0 ? `<span class="badge badge-info">${displayHopCount} hop${displayHopCount !== 1 ? 's' : ''}</span> ` + renderPath(pathHops, effectivePkt.observer_id) : '— (direct)'}</dd>
+        ${effectivePkt.direction ? `<dt>Direction</dt><dd>${escapeHtml(effectivePkt.direction)}</dd>` : ''}
       </dl>
       <div class="detail-actions">
         <button class="copy-link-btn" data-packet-hash="${pkt.hash || ''}" data-packet-id="${pkt.id}" title="Copy link to this packet">🔗 Copy Link</button>
@@ -1872,11 +2006,59 @@
       </div>
 
       ${hasRawHex ? `<div class="hex-legend">${buildHexLegend(ranges)}</div>
-      <div class="hex-dump">${createColoredHexDump(pkt.raw_hex, ranges)}</div>` : ''}
+      <div class="hex-dump">${createColoredHexDump(effectivePkt.raw_hex || pkt.raw_hex, ranges)}</div>` : ''}
 
-      ${hasRawHex ? buildFieldTable(pkt, decoded, pathHops, ranges) : buildDecodedTable(decoded)}
+      ${hasRawHex ? buildFieldTable(effectivePkt.raw_hex ? effectivePkt : pkt, decoded, pathHops, ranges) : buildDecodedTable(decoded)}
+
+      ${observations.length > 1 ? `
+      <div class="detail-observations" style="margin-top:16px">
+        <div style="font-weight:600;margin-bottom:6px">Observations (${observations.length})</div>
+        <table class="detail-obs-table" style="width:100%;border-collapse:collapse;font-size:0.9em">
+          <thead><tr style="border-bottom:1px solid var(--border)">
+            <th style="padding:4px 6px;text-align:left">Observer</th>
+            <th style="padding:4px 6px;text-align:left">Hops</th>
+            <th style="padding:4px 6px;text-align:left">SNR</th>
+            <th style="padding:4px 6px;text-align:left">RSSI</th>
+            <th style="padding:4px 6px;text-align:left">Time</th>
+          </tr></thead>
+          <tbody>${observations.map(o => {
+            const oPath = getParsedPath(o);
+            const isCurrent = currentObs && String(o.id) === String(currentObs.id);
+            return `<tr class="detail-obs-row${isCurrent ? ' observation-current' : ''}" data-obs-id="${o.id}" style="cursor:pointer;${isCurrent ? 'background:var(--accent-bg, rgba(0,122,255,0.1))' : ''}" title="Click to view this observation">
+              <td style="padding:4px 6px">${obsName(o.observer_id)}</td>
+              <td style="padding:4px 6px">${oPath.length}</td>
+              <td style="padding:4px 6px">${o.snr != null ? o.snr + ' dB' : '—'}</td>
+              <td style="padding:4px 6px">${o.rssi != null ? o.rssi + ' dBm' : '—'}</td>
+              <td style="padding:4px 6px">${renderTimestampCell(o.timestamp)}</td>
+            </tr>`;
+          }).join('')}</tbody>
+        </table>
+      </div>` : ''}
+
+      ${observations.length > 1 ? (() => {
+        // Cross-observer aggregate (Option B): show longest observed path across all observers
+        const aggregatePath = getParsedPath(pkt) || [];
+        return `<div class="detail-aggregate" style="margin-top:12px;padding:10px;background:var(--card-bg);border-radius:6px;border:1px solid var(--border);font-size:0.9em">
+          <div style="font-weight:600;margin-bottom:4px;color:var(--text-muted)">Cross-observer aggregate</div>
+          <div>Longest observed path: ${aggregatePath.length ? `${aggregatePath.length} hops — ${renderPath(aggregatePath, pkt.observer_id)}` : '— (direct)'}</div>
+          <div style="font-size:0.8em;color:var(--text-muted);margin-top:2px">Longest path seen across all ${uniqueObservers} observer${uniqueObservers !== 1 ? 's' : ''}</div>
+        </div>`;
+      })() : ''}
     `;
 
+    // Wire up observation row click handlers — re-render detail with clicked observation
+    panel.querySelectorAll('.detail-obs-row').forEach(row => {
+      row.addEventListener('click', () => {
+        const obsId = row.dataset.obsId;
+        selectedObservationId = obsId;
+        // Update URL hash to reflect selected observation (deep linking)
+        const pktHash = pkt.hash || pkt.id;
+        const obsParam = obsId ? `?obs=${obsId}` : '';
+        history.replaceState(null, '', `#/packets/${pktHash}${obsParam}`);
+        renderDetail(panel, data, obsId);
+      });
+    });
+
     // Wire up copy link button
     const copyLinkBtn = panel.querySelector('.copy-link-btn');
     if (copyLinkBtn) {
@@ -1981,38 +2163,43 @@
     // Header section
     rows += sectionRow('Header', 'section-header');
     rows += fieldRow(0, 'Header Byte', '0x' + (buf.slice(0, 2) || '??'), `Route: ${routeTypeName(pkt.route_type)}, Payload: ${payloadTypeName(pkt.payload_type)}`);
-    const pathByte0 = parseInt(buf.slice(2, 4), 16);
-    const hashSizeVal = isNaN(pathByte0) ? '?' : ((pathByte0 >> 6) + 1);
-    const hashCountVal = isNaN(pathByte0) ? '?' : (pathByte0 & 0x3F);
-    rows += fieldRow(1, 'Path Length', '0x' + (buf.slice(2, 4) || '??'), hashCountVal === 0 ? `hash_count=0 (direct advert)` : `hash_size=${hashSizeVal} byte${hashSizeVal !== 1 ? 's' : ''}, hash_count=${hashCountVal}`);
 
-    // Transport codes
-    let off = 2;
-    if (pkt.route_type === 0 || pkt.route_type === 3) {
+    // Transport codes come BEFORE path length for transport routes (bytes 1-4)
+    let off = 1;
+    if (isTransportRoute(pkt.route_type)) {
       rows += sectionRow('Transport Codes', 'section-transport');
       rows += fieldRow(off, 'Next Hop', buf.slice(off * 2, (off + 2) * 2), '');
       rows += fieldRow(off + 2, 'Last Hop', buf.slice((off + 2) * 2, (off + 4) * 2), '');
       off += 4;
     }
 
-    // Path
-    if (pathHops.length > 0) {
-      rows += sectionRow('Path (' + pathHops.length + ' hops)', 'section-path');
-      const pathByte = parseInt(buf.slice(2, 4), 16);
-      const hashSize = (pathByte >> 6) + 1;
-      for (let i = 0; i < pathHops.length; i++) {
-        const hopHtml = HopDisplay.renderHop(pathHops[i], hopNameCache[pathHops[i]]);
+    // Path length byte is at current offset (byte 1 for non-transport, byte 5 for transport)
+    const pathLenOffset = off;
+    const pathByte0 = parseInt(buf.slice(off * 2, off * 2 + 2), 16);
+    const hashSizeVal = isNaN(pathByte0) ? '?' : ((pathByte0 >> 6) + 1);
+    const hashCountVal = isNaN(pathByte0) ? '?' : (pathByte0 & 0x3F);
+    rows += fieldRow(off, 'Path Length', '0x' + (buf.slice(off * 2, off * 2 + 2) || '??'), hashCountVal === 0 ? `hash_count=0 (direct advert)` : `hash_size=${hashSizeVal} byte${hashSizeVal !== 1 ? 's' : ''}, hash_count=${hashCountVal}`);
+    off += 1;
+
+    // Path — derive hop count from path_len byte (firmware truth), not aggregated _parsedPath
+    const hashSize = isNaN(pathByte0) ? 1 : ((pathByte0 >> 6) + 1);
+    if (typeof hashCountVal === 'number' && hashCountVal > 0) {
+      rows += sectionRow('Path (' + hashCountVal + ' hops)', 'section-path');
+      for (let i = 0; i < hashCountVal; i++) {
+        const hopOff = off + i * hashSize;
+        const hex = buf.slice(hopOff * 2, (hopOff + hashSize) * 2).toUpperCase();
+        const hopHtml = HopDisplay.renderHop(hex, hopNameCache[hex]);
         const label = `Hop ${i} — ${hopHtml}`;
-        rows += fieldRow(off + i * hashSize, label, pathHops[i], '');
+        rows += fieldRow(hopOff, label, hex, '');
       }
-      off += hashSize * pathHops.length;
+      off += hashSize * hashCountVal;
     }
 
     // Payload
     rows += sectionRow('Payload — ' + payloadTypeName(pkt.payload_type), 'section-payload');
 
     if (decoded.type === 'ADVERT') {
-      if (hashCountVal !== 0) rows += fieldRow(1, 'Advertised Hash Size', hashSizeVal + ' byte' + (hashSizeVal !== 1 ? 's' : ''), 'From path byte 0x' + (buf.slice(2, 4) || '??') + ' — bits 7-6 = ' + (hashSizeVal - 1));
+      if (hashCountVal !== 0) rows += fieldRow(pathLenOffset, 'Advertised Hash Size', hashSizeVal + ' byte' + (hashSizeVal !== 1 ? 's' : ''), 'From path byte 0x' + (buf.slice(pathLenOffset * 2, pathLenOffset * 2 + 2) || '??') + ' — bits 7-6 = ' + (hashSizeVal - 1));
       rows += fieldRow(off, 'Public Key (32B)', truncate(decoded.pubKey || '', 24), '');
       rows += fieldRow(off + 32, 'Timestamp (4B)', decoded.timestampISO || '', 'Unix: ' + (decoded.timestamp || ''));
       rows += fieldRow(off + 36, 'Signature (64B)', truncate(decoded.signature || '', 24), '');
@@ -2053,6 +2240,10 @@
       rows += fieldRow(off, 'Raw', truncate(buf.slice(off * 2), 40), '');
     }
 
+    if (decoded.anomaly) {
+      rows += `<tr class="anomaly-row" style="background:var(--warning, #f0ad4e); color:#000; font-weight:600;"><td colspan="2">⚠️ Anomaly</td><td colspan="2">${escapeHtml(decoded.anomaly)}</td></tr>`;
+    }
+
     return `<table class="field-table">
       <thead><tr><th scope="col">Offset</th><th scope="col">Field</th><th scope="col">Value</th><th scope="col">Description</th></tr></thead>
       <tbody>${rows}</tbody>
@@ -2144,6 +2335,11 @@
 
     let html = '<div class="byop-decoded">';
 
+    // Anomaly banner
+    if (d.anomaly) {
+      html += '<div class="anomaly-banner" style="background:var(--warning, #f0ad4e); color:#000; padding:8px 12px; border-radius:4px; margin-bottom:8px; font-weight:600;">⚠️ Anomaly: ' + escapeHtml(d.anomaly) + '</div>';
+    }
+
     // Header section
     html += '<div class="byop-section">'
       + '<div class="byop-section-title">Header</div>'

public/roles.js

@@ -394,4 +394,83 @@
     });
     return html;
   };
+
+  // #690 — Clock Skew shared helpers
+  var SKEW_SEVERITY_COLORS = {
+    ok: 'var(--status-green)',
+    warning: 'var(--status-yellow)',
+    critical: 'var(--status-orange)',
+    absurd: 'var(--status-purple)',
+    bimodal_clock: 'var(--status-amber)',
+    no_clock: 'var(--text-muted)'
+  };
+  var SKEW_SEVERITY_LABELS = {
+    ok: 'OK', warning: 'Warning', critical: 'Critical', absurd: 'Absurd', bimodal_clock: 'Bimodal', no_clock: 'No Clock'
+  };
+  var SKEW_SEVERITY_ORDER = { no_clock: 0, bimodal_clock: 1, absurd: 2, critical: 3, warning: 4, ok: 5 };
+
+  window.SKEW_SEVERITY_COLORS = SKEW_SEVERITY_COLORS;
+  window.SKEW_SEVERITY_LABELS = SKEW_SEVERITY_LABELS;
+  window.SKEW_SEVERITY_ORDER = SKEW_SEVERITY_ORDER;
+
+  /** Format skew seconds into human-readable string like "+2m 34s" or "-15h 22m" */
+  window.formatSkew = function(sec) {
+    if (sec == null) return '—';
+    var abs = Math.abs(sec);
+    var sign = sec >= 0 ? '+' : '-';
+    if (abs < 60) return sign + Math.round(abs) + 's';
+    if (abs < 3600) return sign + Math.floor(abs / 60) + 'm ' + Math.round(abs % 60) + 's';
+    if (abs < 86400) return sign + Math.floor(abs / 3600) + 'h ' + Math.round((abs % 3600) / 60) + 'm';
+    return sign + Math.floor(abs / 86400) + 'd ' + Math.round((abs % 86400) / 3600) + 'h';
+  };
+
+  /** Format drift rate as "+X.Xs/day" or "—" if falsy */
+  window.formatDrift = function(secPerDay) {
+    if (!secPerDay) return '—';
+    return (secPerDay >= 0 ? '+' : '') + secPerDay.toFixed(1) + ' s/day';
+  };
+
+  /** Pick the skew value that drives current-health UI: prefer the
+   *  recent-window median (#789, current health) over the all-time median
+   *  (poisoned by historical bad samples). Falls back gracefully if the
+   *  field isn't present (older API responses). */
+  window.currentSkewValue = function(cs) {
+    if (!cs) return null;
+    return cs.recentMedianSkewSec != null ? cs.recentMedianSkewSec : cs.medianSkewSec;
+  };
+
+  /** Render a clock skew badge HTML */
+  window.renderSkewBadge = function(severity, skewSec, cs) {
+    if (!severity) return '';
+    var cls = 'skew-badge skew-badge--' + severity;
+    if (severity === 'no_clock') {
+      return '<span class="' + cls + '" title="Uninitialized RTC — no valid clock">🚫 No Clock</span>';
+    }
+    if (severity === 'bimodal_clock' && cs) {
+      var badPct = cs.goodFraction != null ? Math.round((1 - cs.goodFraction) * 100) : '?';
+      var label = '⏰ ' + window.formatSkew(skewSec);
+      return '<span class="' + cls + '" title="Clock skew: ' + window.formatSkew(skewSec) + ' (bimodal: ' + badPct + '% of recent adverts have nonsense timestamps)">' + label + '</span>';
+    }
+    var label = severity === 'ok' ? '⏰' : '⏰ ' + window.formatSkew(skewSec);
+    return '<span class="' + cls + '" title="Clock skew: ' + window.formatSkew(skewSec) + ' (' + (SKEW_SEVERITY_LABELS[severity] || severity) + ')">' + label + '</span>';
+  };
+
+  /** Render a skew sparkline SVG (inline, word-sized) */
+  window.renderSkewSparkline = function(samples, w, h) {
+    w = w || 120; h = h || 24;
+    if (!samples || samples.length < 2) return '';
+    var values = samples.map(function(s) { return s.skew; });
+    var max = Math.max.apply(null, values.map(function(v) { return Math.abs(v); }).concat([1]));
+    var pts = values.map(function(v, i) {
+      var x = i * (w / Math.max(values.length - 1, 1));
+      var y = h / 2 - (v / max) * (h / 2 - 2);
+      return x.toFixed(1) + ',' + y.toFixed(1);
+    }).join(' ');
+    // Zero line
+    var zeroY = h / 2;
+    return '<svg viewBox="0 0 ' + w + ' ' + h + '" style="width:' + w + 'px;height:' + h + 'px" role="img" aria-label="Clock skew sparkline">' +
+      '<title>Clock skew over time</title>' +
+      '<line x1="0" y1="' + zeroY + '" x2="' + w + '" y2="' + zeroY + '" stroke="var(--border)" stroke-width="0.5" stroke-dasharray="2"/>' +
+      '<polyline points="' + pts + '" fill="none" stroke="var(--accent)" stroke-width="1.5"/></svg>';
+  };
 })();

public/style.css

@@ -11,6 +11,12 @@
   --status-green: #22c55e;
   --status-yellow: #eab308;
   --status-red: #ef4444;
+  --status-orange: #f97316;
+  --status-purple: #a855f7;
+  --status-amber: #f59e0b;
+  --status-amber-light: #fef3c7;
+  --status-amber-text: #92400e;
+  --role-observer: #8b5cf6;
   --accent-hover: #6db3ff;
   --text: #1a1a2e;
   --text-muted: #5b6370;
@@ -41,6 +47,11 @@
     --status-green: #22c55e;
     --status-yellow: #eab308;
     --status-red: #ef4444;
+    --status-orange: #f97316;
+    --status-purple: #a855f7;
+    --status-amber: #f59e0b;
+    --status-amber-light: #422006;
+    --status-amber-text: #fcd34d;
     --surface-0: #0f0f23;
     --surface-1: #1a1a2e;
     --surface-2: #232340;
@@ -65,6 +76,11 @@
   --status-green: #22c55e;
   --status-yellow: #eab308;
   --status-red: #ef4444;
+  --status-orange: #f97316;
+  --status-purple: #a855f7;
+  --status-amber: #f59e0b;
+  --status-amber-light: #422006;
+  --status-amber-text: #fcd34d;
   --surface-0: #0f0f23;
   --surface-1: #1a1a2e;
   --surface-2: #232340;
@@ -338,6 +354,9 @@ a:focus-visible, button:focus-visible, input:focus-visible, select:focus-visible
 }
 .detail-meta dt { color: var(--text-muted); font-size: 11px; text-transform: uppercase; letter-spacing: .3px; }
 .detail-meta dd { font-weight: 500; margin-bottom: 4px; }
+.observation-current { background: var(--accent-bg, rgba(0,122,255,0.1)); font-weight: 600; }
+.detail-obs-row:hover { background: var(--hover-bg, rgba(255,255,255,0.05)); }
+.detail-obs-table th { font-size: 0.8em; text-transform: uppercase; color: var(--text-muted); }
 
 /* === Hex Dump === */
 .hex-dump {
@@ -463,6 +482,14 @@ fieldset.mc-section legend.mc-label { padding: 0; }
 .ch-sidebar-title {
   display: flex; align-items: center; gap: 8px; font-size: 16px; font-weight: 700; margin-bottom: 8px;
 }
+.ch-encrypted-toggle {
+  display: flex; align-items: center; gap: 4px; font-size: 11px; color: var(--text-muted);
+  cursor: pointer; user-select: none; margin-bottom: 4px;
+}
+.ch-encrypted-toggle input { margin: 0; cursor: pointer; }
+.ch-toggle-label { white-space: nowrap; }
+.ch-item.ch-encrypted { opacity: 0.55; }
+.ch-item.ch-encrypted .ch-item-name { font-style: italic; }
 .ch-icon { font-size: 20px; }
 .ch-sidebar-controls { display: flex; align-items: center; gap: 6px; }
 .ch-region-select {
@@ -495,6 +522,9 @@ button.ch-item.selected { background: var(--selected-bg); }
 .ch-item-top { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 2px; }
 .ch-item-name { font-weight: 600; font-size: 14px; }
 .ch-item-time { font-size: 11px; color: var(--text-muted); white-space: nowrap; }
+.ch-remove-btn { background: none; border: none; color: var(--text-muted); cursor: pointer; font-size: 13px; padding: 0 2px; margin-left: 4px; opacity: 0; transition: opacity 0.15s; line-height: 1; }
+button.ch-item:hover .ch-remove-btn { opacity: 0.6; }
+.ch-remove-btn:hover { opacity: 1 !important; color: var(--danger, #dc2626); }
 .ch-item-preview { font-size: 12px; color: var(--text-muted); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
 
 .ch-main { flex: 1; display: flex; flex-direction: column; overflow: hidden; position: relative; }
@@ -679,7 +709,9 @@ button.ch-item.selected { background: var(--selected-bg); }
 .advert-dot {
   width: 10px; height: 10px; border-radius: 50%; flex-shrink: 0; margin-top: 4px;
 }
-.advert-info { font-size: 12px; line-height: 1.5; }
+/* #829: explicit color so text stays readable when inherited color matches card-bg */
+.advert-info { font-size: 12px; line-height: 1.5; color: var(--text); }
+.advert-info a { color: var(--accent); }
 
 /* === Traces Page === */
 .traces-page { padding: 16px; max-width: var(--trace-max-width, 95vw); margin: 0 auto; }
@@ -1097,6 +1129,49 @@ button.ch-item.ch-item-encrypted:hover { opacity: 0.7; }
 button.ch-item.ch-item-encrypted.selected { opacity: 0.8; }
 button.ch-item.ch-item-encrypted .ch-badge { filter: grayscale(0.6); }
 
+/* Channel key input (#725 M2) */
+.ch-key-input {
+  flex: 1;
+  min-width: 0;
+  box-sizing: border-box;
+  padding: 6px 8px;
+  border: 1px solid var(--border);
+  border-radius: 6px 0 0 6px;
+  background: var(--card-bg);
+  color: var(--text);
+  font-size: 12px;
+  font-family: inherit;
+}
+.ch-key-input:focus {
+  outline: 2px solid var(--accent, #3b82f6);
+  outline-offset: -1px;
+  border-color: var(--accent, #3b82f6);
+}
+.ch-key-input::placeholder { color: var(--text-muted); }
+.ch-key-input-wrap { margin-bottom: 4px; }
+.ch-wrong-key { color: var(--danger, #ef4444); font-weight: 500; }
+
+/* Add channel form (#759) */
+.ch-add-form { margin: 0; }
+.ch-add-label { display: block; font-weight: 600; font-size: 13px; color: var(--text); margin-bottom: 4px; }
+.ch-key-input, .ch-add-btn { height: 32px; box-sizing: border-box; }
+.ch-add-row { display: flex; align-items: stretch; }
+.ch-add-btn {
+  width: 32px; height: 32px; flex-shrink: 0;
+  border: 1px solid var(--accent, #3b82f6); border-left: none;
+  border-radius: 0 6px 6px 0;
+  background: var(--accent, #3b82f6); color: #fff;
+  font-size: 18px; font-weight: 700; line-height: 1;
+  cursor: pointer; display: flex; align-items: center; justify-content: center;
+}
+.ch-add-btn:hover { opacity: 0.85; }
+.ch-add-hint { font-size: 11px; color: var(--text-muted); margin-top: 4px; line-height: 1.3; }
+.ch-add-status { font-size: 12px; margin-top: 4px; padding: 4px 6px; border-radius: 4px; }
+.ch-add-status--loading { color: var(--text-muted); }
+.ch-add-status--success { color: var(--success, #22c55e); }
+.ch-add-status--warn { color: var(--warning, #eab308); }
+.ch-add-status--error { color: var(--danger, #ef4444); }
+
 /* Touch-friendly tappable elements */
 .ch-tappable {
   cursor: pointer;
@@ -1362,7 +1437,9 @@ button.ch-item.ch-item-encrypted .ch-badge { filter: grayscale(0.6); }
 .hop-conflict-name { font-weight: 600; flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
 .hop-conflict-dist { font-size: 11px; color: var(--text-muted); font-family: var(--mono); white-space: nowrap; }
 .hop-conflict-pk { font-size: 10px; color: var(--text-muted); font-family: var(--mono); }
-.hop-unreliable { opacity: 0.5; text-decoration: line-through; }
+.hop-unreliable { opacity: 0.85; }
+.hop-unreliable-btn { background: none; border: none; color: var(--status-yellow, #f59e0b); font-size: 13px;
+  cursor: help; vertical-align: middle; margin-left: 2px; padding: 0 2px; line-height: 1; }
 .hop-global-fallback { border-bottom: 1px dashed var(--status-red); }
 .hop-current { font-weight: 700 !important; color: var(--accent) !important; }
 
@@ -2211,3 +2288,25 @@ th[data-sort-key] { cursor: pointer; user-select: none; }
 th[data-sort-key]:hover { background: var(--hover-bg, rgba(255,255,255,0.05)); }
 th.sort-active { color: var(--accent, #60a5fa); }
 .sort-arrow { font-size: 0.75em; opacity: 0.8; }
+
+/* #690 — Clock Skew badges & fleet table */
+.skew-badge { display: inline-block; font-size: 10px; padding: 1px 5px; border-radius: 3px; margin-left: 4px; font-weight: 600; white-space: nowrap; }
+.skew-badge--ok { background: var(--status-green); color: #fff; }
+.skew-badge--warning { background: var(--status-yellow); color: #000; }
+.skew-badge--critical { background: var(--status-orange); color: #fff; }
+.skew-badge--absurd { background: var(--status-purple); color: #fff; }
+.skew-badge--no_clock { background: var(--text-muted); color: #fff; }
+.skew-badge--bimodal_clock { background: var(--status-amber-light); color: var(--status-amber-text); border: 1px solid var(--status-amber); }
+
+.skew-detail-section { padding: 10px 16px; margin-bottom: 8px; }
+.skew-sparkline-wrap { margin-top: 6px; }
+.skew-sparkline-wrap svg { display: block; }
+
+
+.clock-fleet-row--warning { background: color-mix(in srgb, var(--status-yellow) 10%, transparent); }
+.clock-fleet-row--critical { background: color-mix(in srgb, var(--status-orange) 10%, transparent); }
+.clock-fleet-row--absurd { background: color-mix(in srgb, var(--status-purple) 10%, transparent); }
+.clock-fleet-row--no_clock { background: color-mix(in srgb, var(--text-muted) 10%, transparent); }
+
+.clock-filter-btn { font-size: 12px; padding: 3px 8px; border: 1px solid var(--border); border-radius: 4px; background: var(--card-bg, #fff); color: var(--text); cursor: pointer; margin-right: 4px; }
+.clock-filter-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }

qa/README.md

@@ -0,0 +1,45 @@
+# CoreScope QA artifacts
+
+Project-specific assets for the [`qa-suite`](https://github.com/Kpa-clawbot/ai-sdlc/tree/master/skills/qa-suite) skill.
+
+## Layout
+
+```
+qa/
+├── README.md                  ← this file
+├── plans/
+│   └── <release>.md           ← per-release test plans (one file per RC)
+└── scripts/
+    └── api-contract-diff.sh   ← CoreScope-tuned API contract diff
+```
+
+## How to run
+
+```
+qa staging              # use the latest plans/v*-rc.md against staging
+qa pr 806               # use plans/pr-806.md if it exists, else latest plans/v*-rc.md
+qa v3.6.0-rc            # use plans/v3.6.0-rc.md
+```
+
+The parent agent loads the qa-suite skill, which reads:
+1. The plan file from `qa/plans/`
+2. Bundled scripts from `qa/scripts/`
+3. The reusable engine + qa-engineer persona from the skill itself
+
+## Adding a new plan
+
+For each release candidate, copy the latest `plans/v*-rc.md` to `plans/<new-tag>.md` and update:
+- The commit-range header (`vN.M..master`)
+- Any new sections for new features in the release
+- The "Test data" section if new fixture types are needed
+- The GO criteria (which sections are blockers)
+
+## Adding a new script
+
+Custom scripts go in `qa/scripts/` with `mode=auto: <script-name>` referenced from the plan. The qa-engineer subagent runs them with two args: `BASELINE_URL TARGET_URL`.
+
+Authoring rules from the qa-suite skill:
+- 4-way error classification: `curl-failed` / `parse-empty` / `shape-diff` / field-missing
+- Distinguish HTTP errors from jq parse failures
+- Don't silence stderr — script bugs must surface
+- Exit code = number of failures

qa/plans/v3.6.0-rc.md

@@ -0,0 +1,108 @@
+# Plan: v3.6.0-rc
+
+Targets the changes between v3.5.1 and v3.6.0 candidate (~34 commits).
+
+## Test data
+The qa-engineer should pick concrete test fixtures at run time and include them in the report:
+- **Pivot node pubkey**: pick the top-result from `/api/nodes?limit=20&sort=advert_count` that has `role=repeater` AND a non-zero `totalPaths` from `/api/nodes/{pk}/paths`. Used for sections 5.1, 8.1, 8.2.
+- **Multi-role pubkey** (section 8.6): pick a node whose pubkey appears in BOTH `/api/observers` and `/api/nodes?role=repeater`. If none → mark 8.6 `needs-human`.
+- **Sample packet hash**: `/api/packets?limit=1` → `.packets[0].hash`. Used for sections 3.x.
+- **Channel sample**: pick a channel name from `/api/channels` (if endpoint exists) or scrape `/#channels` page.
+
+Record every fixture used in the final report so failures are reproducible.
+
+## Sections
+
+### 1. Memory & Load
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 1.1 | Container with **3 GB** limit starts on heaviest available DB | No OOM, steady state under limit. Note: 1 GB cap is unrealistic without `GOMEMLIMIT` and bounded cold-load — see #836 | #806/#836 | human |
+| 1.2 | Hit `/debug/pprof/heap` after Load completes; run `pprof-snapshot.sh` | `unmarshalResolvedPath` absent from top-15 inuse_space; `Load()`-attributed inuse_space ≤ 250 MB on staging-sized DB (~1.5M obs); total heap < 1 GB | #806 | auto: pprof-snapshot.sh |
+| 1.3 | Set tight `MaxLoadMemMB`, restart | Load stops gracefully at budget; server still serves `/api/stats` 200 | #790 | human |
+| 1.4 | Watch `processRSSMB` (from `/api/stats`) vs procfs RSS over ingest+eviction cycles | `processRSSMB` tracks `cat /proc/$(pidof corescope)/status | awk '/VmRSS/{print $2}'` (kB → MB) within ±20% across one full eviction cycle. Note: `storeDataMB` (formerly `trackedMB`) is the in-store packet byte estimate and is expected to be a **subset** of RSS, not equal to it. | #751, #832 | human |
+| 1.5 | Run 30 min under live ingest | Sawtooth heap pattern (≥1 eviction-driven dip), not monotonic ramp | #806/#807 | human |
+
+### 2. API contract
+Run `scripts/api-contract-diff.sh BASELINE_URL TARGET_URL` once. Report the script's exit code; nonzero = failures.
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 2.1 | api-contract-diff baseline vs target | Exit code 0; all endpoints carry `resolved_path` where expected | #806 | auto: api-contract-diff.sh |
+| 2.2 | WebSocket `/ws` carries `resolved_path` on broadcasts | Run JS hook in browser console: `(function(){let n=0,r=0; const W=WebSocket; window.WebSocket=function(...a){const s=new W(...a); s.addEventListener('message',e=>{n++; try{const m=JSON.parse(e.data); if(m && (m.resolved_path !== undefined || (m.observations||[]).some(o=>o.resolved_path!==undefined))) r++;}catch{}}); return s;}; window.__wsCount=()=>({n,r});})()` then navigate to `/`, wait 30s, eval `__wsCount()` — `r` must be ≥ 1 if `n` ≥ 1 | #806 | browser |
+
+### 3. Decoder & hashing
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 3.1 | Recompute content hashes for sample of recent packets vs stored | All match (hash uses payload-type bits only) | #787 | human |
+| 3.2 | Inspect a TRACE packet detail panel | path_json length matches path_sz from flags byte | #732 | browser |
+| 3.3 | Check `hash_size` on transport-route packet AND zero-hop advert | Correct hash_size detected | #747 | browser |
+| 3.4 | Field-table column offsets for transport-route packet | Snapshot of detail panel: each field row has nonzero `offset`/`length` cells AND offsets monotonically increase | #766 | browser |
+| 3.5 | Corrupt advert ingest log check | Rejected, counted, no DB entry | #794 | human |
+| 3.6 | Public channel packet rendering | No empty/garbled decode | #761 | browser |
+
+### 4. Channels (#725)
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 4.1 | Channel list — full message history loads from DB | Past messages persist across reload | #726 | browser |
+| 4.2 | Add custom channel via UI (then remove it as teardown) | Channel appears, encrypted msgs decrypt; teardown removes it cleanly. STAGING ONLY. | #733 | browser |
+| 4.3 | PSK channel add + channel removal (already a self-teardown) | Both work, UI state correct after | #750 | browser |
+| 4.4 | Deep link to encrypted channel without key | Lock message shows | #783 | browser |
+| 4.5 | Undecryptable msgs hidden by default + toggle | Hidden default; toggle shows | #728 | browser |
+| 4.6 | Add-channel button + hint + status feedback | All present | #760 | browser |
+| 4.7 | Filter packets by channel | Functional: filter applies, packet count drops; performance: response time ≤ 500 ms for `/api/packets?channel=<name>&limit=100` (timed via `curl -w '%{time_total}'`) | #762/#763 | browser+auto |
+
+### 5. Clock skew (#690)
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 5.1 | Node detail clock-skew badge + sparkline | Both render | #746/#752 | browser |
+| 5.2 | Analytics fleet clock-skew page | Renders, epoch-0 filtered | #769 | browser |
+| 5.3 | Outlier sample doesn't poison median | Sanity caps respected; severity uses `recentMedianSkewSec` (#789), not all-time `medianSkewSec` | #769/#789 | human |
+| 5.4 | Roles page clock-skew indicator | Renders | #752 | browser |
+
+### 6. Observers
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 6.1 | Observer with no packets in N days disappears after retention sweep | Removed | #764 | human |
+| 6.2 | Analytics observer-graph (M1+M2) | Renders (`#observerGraph` element present at `public/analytics.js:2048-2051`) | #774 | browser |
+
+### 7. Multi-byte hash adopters
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 7.1 | Hash Usage Matrix collision details for all hash sizes | Click cell → colliding pubkeys shown | #758 | browser |
+| 7.2 | Multi-byte adopter table includes all node types | Repeaters, room servers, sensors all present | #767 | browser |
+| 7.3 | Role column reflects multi-byte adoption + advert precedence | For 3 sample multi-byte adopter pubkeys (from #758 matrix), the Role column on `/#nodes` matches the role inferred from their latest advert flags via `/api/nodes/{pk}/health` | #767 | browser |
+
+### 8. Frontend nav & deep linking
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 8.1 | Click node on map/list — URL hash updates, panel opens | Hash matches | #739 | browser |
+| 8.2 | Open saved deep-link to a node | Full-screen detail view opens (post-#823: desktop deep links match the Details-link path) | #739/#823 | browser |
+| 8.3 | Packets page filter URL hash | Reload preserves filters | #740 | browser |
+| 8.4 | Details/Analytics links in node detail panel | Navigate without router glitch | #779/#785 | browser |
+| 8.5 | Neighbor graph slider | Persists across reloads, default 0.7 | #776 | browser |
+| 8.6 | Repeater that's also observer | Single map marker | #745 | browser |
+| 8.7 | Side-panel "Recent Packets" — click any entry, lands on packet detail (no 404), entry text is readable in current theme | DB-fallback works (#827); `.advert-info` has explicit color (#829) | #827/#829 | browser |
+
+### 9. Geofilter & customizer
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 9.1 | Customize → "Open geofilter builder" link | Opens app-served builder | #735 | browser |
+| 9.2 | Build a filter, save, reload (STAGING ONLY; teardown: delete the saved filter) | Persists across reload; teardown removes it | #735 | browser |
+| 9.3 | Geofilter docs page | Renders, content matches behavior | #734 | browser |
+
+### 10. Node blacklist
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 10.1 | Add node pubkey to nodeBlacklist config; restart | Hidden from listings/map/neighbor graph | #742 | auto: blacklist-test.sh |
+| 10.2 | Packets still in DB | Yes (filter not delete) | #742 | auto: blacklist-test.sh |
+
+`blacklist-test.sh` covers both 10.1 and 10.2 in one run. Required env: `TEST_NODE_PUBKEY` (hex, of a real visible node on TARGET), `TARGET_SSH_HOST`, `TARGET_CONFIG_PATH`, `TARGET_CONTAINER`. Optional: `TARGET_DB_PATH` or `ADMIN_API_TOKEN` for §10.2 probe; `TARGET_SSH_KEY` (default `/root/.ssh/id_ed25519`). Mandatory teardown removes the pubkey and verifies the node returns to listings.
+
+### 11. Deploy/ops
+| # | Step | Pass criteria | Source | Mode |
+|---|---|---|---|---|
+| 11.1 | Force-redeploy staging | Container removed cleanly even if `docker run`, not compose. Playwright E2E `Desktop: deep link #/nodes/{pubkey} opens full-screen detail view` passes (updated #833 — was asserting old pre-#823 split-panel behavior). | fa348ef/#833 | human |
+
+## GO criteria
+- Sections 1.2, 2, 3 must all pass — release blockers
+- Section 4 (channels) — any visible regression must be fixed before tag
+- Other sections: file follow-up issues; decide per-item whether to tag with known issues

qa/scripts/api-contract-diff.sh

@@ -0,0 +1,134 @@
+#!/usr/bin/env bash
+# api-contract-diff.sh — diff CoreScope API endpoints between two deployments.
+# Usage: api-contract-diff.sh BASELINE_URL TARGET_URL [-k AUTH_HEADER]
+#
+# Compares JSON shape (recursive key set) per endpoint and asserts presence of
+# `resolved_path` where contract requires it. Prints a per-endpoint result line
+# (✅/❌) and a summary. Exit code = number of failures.
+#
+# Distinguishes:
+#   curl-failed  → HTTP error or network timeout (real outage)
+#   parse-empty  → curl succeeded but response shape unexpected (probable
+#                  contract drift in this script or in the API)
+#   shape-diff   → recursive key set differs between baseline and target
+#   rp-missing   → resolved_path absent on target where it was promised
+#
+# PUBLIC repo: do not commit URLs or keys here. Caller passes them.
+
+set -uo pipefail
+
+OLD="${1:-}"; NEW="${2:-}"
+[[ -z "$OLD" || -z "$NEW" ]] && { echo "usage: $0 BASELINE_URL TARGET_URL [-k AUTH_HEADER]" >&2; exit 2; }
+shift 2 || true
+AUTH=""
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    -k) AUTH="$2"; shift 2 ;;
+    *) echo "unknown arg: $1" >&2; exit 2 ;;
+  esac
+done
+
+TMP=$(mktemp -d); trap 'rm -rf "$TMP"' EXIT
+
+# Wrapper: fetch URL, return body on stdout, exit 1 on HTTP error / timeout.
+fetch() {
+  local url="$1" out="$2"
+  local code
+  code=$(curl -s -m 30 -o "$out" -w "%{http_code}" ${AUTH:+-H "$AUTH"} "$url" 2>/dev/null) || code="000"
+  if [[ "$code" != "2"* ]]; then
+    echo "  HTTP $code"
+    return 1
+  fi
+  return 0
+}
+
+# Seed lookups from TARGET (so the picked IDs are guaranteed present there).
+seed_packets="$TMP/seed_packets.json"
+seed_observers="$TMP/seed_observers.json"
+seed_nodes="$TMP/seed_nodes.json"
+
+if ! fetch "$NEW/api/packets?limit=1" "$seed_packets"; then echo "seed /api/packets failed" >&2; fi
+if ! fetch "$NEW/api/observers"       "$seed_observers"; then echo "seed /api/observers failed" >&2; fi
+if ! fetch "$NEW/api/nodes?limit=1"   "$seed_nodes"; then echo "seed /api/nodes failed" >&2; fi
+
+HASH=$(jq -r '.packets[0].hash // empty'         "$seed_packets"   2>/dev/null || true)
+OBSID=$(jq -r '.observers[0].id // empty'        "$seed_observers" 2>/dev/null || true)
+NODEPK=$(jq -r '.nodes[0].public_key // empty'   "$seed_nodes"     2>/dev/null || true)
+
+[[ -z "$HASH"   ]] && echo "warn: no packet hash from /api/packets — packet-detail endpoints will be skipped" >&2
+[[ -z "$OBSID"  ]] && echo "warn: no observer id   from /api/observers — observer-detail endpoints will be skipped" >&2
+[[ -z "$NODEPK" ]] && echo "warn: no node pubkey   from /api/nodes — node-detail endpoints will be skipped" >&2
+
+# Endpoints to diff: path | jq filter (selects subobject to compare) | RP-required(yes/no)
+declare -a ENDPOINTS
+ENDPOINTS+=("/api/packets?limit=20|.packets[0]|yes")
+ENDPOINTS+=("/api/packets?limit=20&expandObservations=true|.packets[0]|yes")
+ENDPOINTS+=("/api/observers|.observers[0]|no")
+[[ -n "$HASH"   ]] && ENDPOINTS+=("/api/packets/$HASH|.|yes")
+[[ -n "$OBSID"  ]] && ENDPOINTS+=("/api/observers/$OBSID|.|no")
+[[ -n "$OBSID"  ]] && ENDPOINTS+=("/api/observers/$OBSID/analytics|.|no")
+[[ -n "$NODEPK" ]] && ENDPOINTS+=("/api/nodes/$NODEPK/health|.recentPackets[0]|yes")
+[[ -n "$NODEPK" ]] && ENDPOINTS+=("/api/nodes/$NODEPK/paths|.|no")
+
+# Strip volatile fields (timestamps + counters) from a JSON value.
+STRIP='walk(if type=="object" then del(.timestamp, .first_seen, .last_seen, .last_heard, .updated_at, .server_time, .packet_count, .packetsLastHour, .uptime_secs, .battery_mv, .noise_floor, .observation_count, .advert_count) else . end)'
+
+fails=0
+for ep in "${ENDPOINTS[@]}"; do
+  IFS='|' read -r path filter need_rp <<<"$ep"
+  echo "=== $path  (resolved_path required: $need_rp) ==="
+
+  oldfile="$TMP/old.json"; newfile="$TMP/new.json"
+  if ! fetch "$OLD$path" "$oldfile"; then echo "  ❌ baseline curl-failed"; fails=$((fails+1)); continue; fi
+  if ! fetch "$NEW$path" "$newfile"; then echo "  ❌ target curl-failed";   fails=$((fails+1)); continue; fi
+
+  # Selector + strip on each side. jq stderr is preserved so script bugs surface.
+  oldj=$(jq "$filter | $STRIP" "$oldfile")
+  jq_old_rc=$?
+  newj=$(jq "$filter | $STRIP" "$newfile")
+  jq_new_rc=$?
+
+  if [[ $jq_old_rc -ne 0 ]]; then
+    echo "  ❌ baseline jq-error (filter='$filter') — likely script bug or API shape changed"
+    fails=$((fails+1)); continue
+  fi
+  if [[ $jq_new_rc -ne 0 ]]; then
+    echo "  ❌ target jq-error (filter='$filter') — likely script bug or API shape changed"
+    fails=$((fails+1)); continue
+  fi
+  if [[ -z "$oldj" || "$oldj" == "null" ]]; then
+    echo "  ❌ baseline parse-empty (filter returned empty/null; check API shape)"
+    fails=$((fails+1)); continue
+  fi
+  if [[ -z "$newj" || "$newj" == "null" ]]; then
+    echo "  ❌ target parse-empty (filter returned empty/null; check API shape)"
+    fails=$((fails+1)); continue
+  fi
+
+  # Recursive key-set diff. Canonicalize array indices (numbers) → "[]" so two
+  # different sample responses with different array lengths don't false-positive.
+  KEYS_FILTER='[paths(scalars or type=="null" or (type=="array" and length==0) or (type=="object" and length==0)) | map(if type=="number" then "[]" else . end) | join(".")] | unique | .[]'
+  oldkeys=$(echo "$oldj" | jq -r "$KEYS_FILTER" | sort -u)
+  newkeys=$(echo "$newj" | jq -r "$KEYS_FILTER" | sort -u)
+  if ! diff <(echo "$oldkeys") <(echo "$newkeys") >/dev/null; then
+    echo "  ❌ shape-diff (key set differs):"
+    diff <(echo "$oldkeys") <(echo "$newkeys") | sed 's/^/    /'
+    fails=$((fails+1))
+    continue
+  fi
+
+  # If RP expected, assert present on target (any value, may be null).
+  if [[ "$need_rp" == "yes" ]]; then
+    if ! echo "$newj" | jq -e '.. | objects | select(has("resolved_path")) | .resolved_path' >/dev/null 2>&1; then
+      echo "  ❌ rp-missing (resolved_path not present anywhere in selector)"
+      fails=$((fails+1))
+      continue
+    fi
+  fi
+
+  echo "  ✅ ok"
+done
+
+echo
+echo "failures: $fails / ${#ENDPOINTS[@]}"
+exit $fails

qa/scripts/blacklist-test.sh

@@ -0,0 +1,271 @@
+#!/usr/bin/env bash
+# blacklist-test.sh — verify nodeBlacklist hides a pubkey from API surface
+# while retaining its packets in the DB. Implements QA plan §10.1 + §10.2.
+#
+# Usage:
+#   blacklist-test.sh BASELINE_URL TARGET_URL
+#
+# BASELINE_URL is currently unused for assertions but kept as a positional
+# arg for parity with other qa-suite scripts (always called with two URLs).
+#
+# Required env (target host control + test data):
+#   TEST_NODE_PUBKEY      — hex pubkey of a real, currently-visible node on TARGET_URL
+#   TARGET_SSH_HOST       — e.g. runner@example
+#   TARGET_SSH_KEY        — path to ssh private key (default: /root/.ssh/id_ed25519)
+#   TARGET_CONFIG_PATH    — absolute path to config.json on the target
+#   TARGET_CONTAINER      — docker container name on the target
+# Optional env:
+#   TARGET_DB_PATH        — sqlite db path on the target (for §10.2 sqlite probe)
+#   ADMIN_API_TOKEN       — if /api/admin/transmissions exists, use it instead of ssh+sqlite
+#                            (read from env, not argv — never appears in ps)
+#   CURL_TIMEOUT          — per-request curl timeout, seconds (default 60)
+#   RESTART_WAIT_S        — max wait for /api/stats after restart (default 120)
+#
+# Distinguishes:
+#   ssh-failed     → cannot reach/control target
+#   restart-stuck  → /api/stats not 200 within RESTART_WAIT_S
+#   hide-failed    → blacklisted pubkey still surfaced via API (§10.1 fail)
+#   retain-failed  → blacklisted pubkey absent from DB (§10.2 fail)
+#   teardown-failed→ post-test removal did not restore listing
+#
+# Exit code = number of failures (0 = pass).
+# PUBLIC repo: zero PII — no real pubkeys, IPs, or hostnames as defaults.
+
+set -uo pipefail
+
+BASELINE_URL="${1:-}"
+TARGET_URL="${2:-}"
+if [[ -z "$BASELINE_URL" || -z "$TARGET_URL" ]]; then
+  echo "usage: $0 BASELINE_URL TARGET_URL  (TEST_NODE_PUBKEY+TARGET_* via env)" >&2
+  exit 2
+fi
+
+TEST_PUBKEY="${TEST_NODE_PUBKEY:-}"
+TARGET_SSH_HOST="${TARGET_SSH_HOST:-}"
+TARGET_SSH_KEY="${TARGET_SSH_KEY:-/root/.ssh/id_ed25519}"
+TARGET_CONFIG_PATH="${TARGET_CONFIG_PATH:-}"
+TARGET_CONTAINER="${TARGET_CONTAINER:-}"
+TARGET_DB_PATH="${TARGET_DB_PATH:-}"
+ADMIN_API_TOKEN="${ADMIN_API_TOKEN:-}"
+
+if [[ -z "$TEST_PUBKEY" || -z "$TARGET_SSH_HOST" || -z "$TARGET_CONFIG_PATH" || -z "$TARGET_CONTAINER" ]]; then
+  echo "error: TEST_NODE_PUBKEY, TARGET_SSH_HOST, TARGET_CONFIG_PATH, TARGET_CONTAINER are required" >&2
+  exit 2
+fi
+
+# Hard input validation — these strings are interpolated into remote shell/SQL.
+# Pubkey must be hex (MeshCore pubkeys are hex-encoded ed25519 prefixes).
+if ! [[ "$TEST_PUBKEY" =~ ^[0-9a-fA-F]+$ ]]; then
+  echo "error: TEST_NODE_PUBKEY must be hex (got: redacted)" >&2
+  exit 2
+fi
+# Container name must match docker's allowed chars: [a-zA-Z0-9][a-zA-Z0-9_.-]*
+if ! [[ "$TARGET_CONTAINER" =~ ^[a-zA-Z0-9][a-zA-Z0-9_.-]*$ ]]; then
+  echo "error: TARGET_CONTAINER has illegal chars" >&2
+  exit 2
+fi
+# Config path must be an absolute, sane path (no spaces, quotes, $, ;, etc.).
+if ! [[ "$TARGET_CONFIG_PATH" =~ ^/[A-Za-z0-9_./-]+$ ]]; then
+  echo "error: TARGET_CONFIG_PATH must be a sane absolute path" >&2
+  exit 2
+fi
+if [[ -n "$TARGET_DB_PATH" ]] && ! [[ "$TARGET_DB_PATH" =~ ^/[A-Za-z0-9_./-]+$ ]]; then
+  echo "error: TARGET_DB_PATH must be a sane absolute path" >&2
+  exit 2
+fi
+
+CURL_TIMEOUT="${CURL_TIMEOUT:-60}"
+RESTART_WAIT_S="${RESTART_WAIT_S:-120}"
+
+SSH_OPTS=(-i "$TARGET_SSH_KEY" -o StrictHostKeyChecking=accept-new -o ConnectTimeout=15 -o BatchMode=yes)
+ssh_t() { ssh "${SSH_OPTS[@]}" "$TARGET_SSH_HOST" "$@"; }
+
+TMP=$(mktemp -d)
+fails=0
+TEARDOWN_DONE=0
+
+# -----------------------------------------------------------------------------
+# Teardown — MANDATORY in all exit paths.
+# -----------------------------------------------------------------------------
+teardown() {
+  local rc=$?
+  if [[ "$TEARDOWN_DONE" == "1" ]]; then rm -rf "$TMP"; exit "$rc"; fi
+  TEARDOWN_DONE=1
+  echo "=== teardown: removing $TEST_PUBKEY from nodeBlacklist ==="
+  if remove_from_blacklist && restart_target && wait_for_stats; then
+    if node_visible; then
+      echo "  ✅ teardown ok — node returned to listings"
+    else
+      echo "  ❌ teardown-failed: node still hidden after removal"
+      rc=$((rc + 1))
+    fi
+  else
+    echo "  ❌ teardown-failed: could not restore config / restart / stats"
+    rc=$((rc + 1))
+  fi
+  rm -rf "$TMP"
+  exit "$rc"
+}
+trap teardown EXIT INT TERM
+
+# -----------------------------------------------------------------------------
+# Helpers
+# -----------------------------------------------------------------------------
+fetch_code() {
+  local url="$1" out="$2"
+  curl -s -m "$CURL_TIMEOUT" -o "$out" -w "%{http_code}" "$url" 2>/dev/null || echo "000"
+}
+
+wait_for_stats() {
+  local deadline code
+  echo "  waiting up to ${RESTART_WAIT_S}s for $TARGET_URL/api/stats ..."
+  deadline=$(( $(date +%s) + RESTART_WAIT_S ))
+  while (( $(date +%s) < deadline )); do
+    code=$(fetch_code "$TARGET_URL/api/stats" "$TMP/stats.json")
+    if [[ "$code" == "200" ]]; then echo "  stats OK"; return 0; fi
+    sleep 3
+  done
+  echo "  ❌ restart-stuck: /api/stats never returned 200"
+  return 1
+}
+
+restart_target() {
+  echo "  restarting container $TARGET_CONTAINER ..."
+  # TARGET_CONTAINER is validated above; still quote defensively.
+  if ! ssh_t "docker restart $(printf %q "$TARGET_CONTAINER")" >/dev/null; then
+    echo "  ❌ ssh-failed: docker restart failed"
+    return 1
+  fi
+  return 0
+}
+
+# Mutate config.json on target. Values pass via env (printf %q + single-quoted
+# heredoc) so $TEST_PUBKEY etc. never enter the remote shell as code.
+set_blacklist_state() {
+  local mode="$1"  # add | remove
+  ssh_t "CFG=$(printf %q "$TARGET_CONFIG_PATH") PK=$(printf %q "$TEST_PUBKEY") MODE=$(printf %q "$mode") bash -s" <<'REMOTE'
+set -euo pipefail
+TMP="$(mktemp)"
+trap 'rm -f "$TMP"' EXIT
+if command -v jq >/dev/null; then
+  if [ "$MODE" = "add" ]; then
+    jq --arg pk "$PK" '.nodeBlacklist = ((.nodeBlacklist // []) + [$pk] | unique)' "$CFG" > "$TMP"
+  else
+    jq --arg pk "$PK" '.nodeBlacklist = ((.nodeBlacklist // []) - [$pk])' "$CFG" > "$TMP"
+  fi
+else
+  python3 - "$CFG" "$PK" "$MODE" "$TMP" <<'PY'
+import json, sys
+cfg, pk, mode, out = sys.argv[1:]
+with open(cfg) as f: d = json.load(f)
+bl = list(dict.fromkeys(d.get("nodeBlacklist") or []))
+if mode == "add":
+    if pk not in bl: bl.append(pk)
+else:
+    bl = [x for x in bl if x != pk]
+d["nodeBlacklist"] = bl
+with open(out, "w") as f: json.dump(d, f, indent=2)
+PY
+fi
+# Preserve mode and ownership; mv across same FS is atomic.
+chmod --reference="$CFG" "$TMP" 2>/dev/null || true
+chown --reference="$CFG" "$TMP" 2>/dev/null || true
+mv "$TMP" "$CFG"
+trap - EXIT
+REMOTE
+  local rc=$?
+  if (( rc != 0 )); then
+    echo "  ❌ ssh-failed: could not edit $TARGET_CONFIG_PATH ($mode)"
+    return 1
+  fi
+  return 0
+}
+
+add_to_blacklist()      { set_blacklist_state add; }
+remove_from_blacklist() { set_blacklist_state remove; }
+
+node_visible() {
+  # Returns 0 if the pubkey is currently visible via API.
+  local code
+  code=$(fetch_code "$TARGET_URL/api/nodes/$TEST_PUBKEY" "$TMP/node.json")
+  if [[ "$code" == "200" ]]; then return 0; fi
+  fetch_code "$TARGET_URL/api/nodes?limit=10000" "$TMP/nodes.json" >/dev/null
+  if grep -qF -- "\"$TEST_PUBKEY\"" "$TMP/nodes.json" 2>/dev/null; then
+    return 0
+  fi
+  return 1
+}
+
+# -----------------------------------------------------------------------------
+# §10.1 — hide
+# -----------------------------------------------------------------------------
+echo "=== §10.1 add $TEST_PUBKEY to nodeBlacklist ==="
+if ! add_to_blacklist; then fails=$((fails+1)); exit "$fails"; fi
+if ! restart_target;    then fails=$((fails+1)); exit "$fails"; fi
+if ! wait_for_stats;    then fails=$((fails+1)); exit "$fails"; fi
+
+detail_code=$(fetch_code "$TARGET_URL/api/nodes/$TEST_PUBKEY" "$TMP/detail.json")
+list_code=$(fetch_code "$TARGET_URL/api/nodes?limit=10000" "$TMP/list.json")
+in_list=0
+if [[ "$list_code" == "200" ]] && grep -qF -- "\"$TEST_PUBKEY\"" "$TMP/list.json"; then
+  in_list=1
+fi
+if [[ "$detail_code" == "404" || "$in_list" == "0" ]]; then
+  echo "  ✅ hide ok: detail=$detail_code in_list=$in_list"
+else
+  echo "  ❌ hide-failed: detail=$detail_code in_list=$in_list — pubkey still surfaced"
+  fails=$((fails+1))
+fi
+
+topo_code=$(fetch_code "$TARGET_URL/api/topology" "$TMP/topo.json")
+if [[ "$topo_code" != "200" ]]; then
+  echo "  ⚠️  /api/topology HTTP $topo_code — skipping topology assertion"
+elif grep -qF -- "$TEST_PUBKEY" "$TMP/topo.json"; then
+  echo "  ❌ hide-failed: /api/topology references blacklisted pubkey"
+  fails=$((fails+1))
+else
+  echo "  ✅ topology clean"
+fi
+
+# -----------------------------------------------------------------------------
+# §10.2 — DB retain
+# -----------------------------------------------------------------------------
+echo "=== §10.2 verify packets retained in DB ==="
+count=""
+if [[ -n "$ADMIN_API_TOKEN" ]]; then
+  # Read auth header from stdin so the token never enters argv (ps-safe).
+  code=$(printf 'header = "Authorization: Bearer %s"\n' "$ADMIN_API_TOKEN" | \
+    curl -s -m "$CURL_TIMEOUT" -K - -o "$TMP/admin.json" -w "%{http_code}" \
+      "$TARGET_URL/api/admin/transmissions?from_node=$TEST_PUBKEY&count=1" 2>/dev/null || echo "000")
+  if [[ "$code" == "200" ]]; then
+    count=$(jq -r '.count // ((.transmissions // []) | length)' "$TMP/admin.json" 2>/dev/null || echo "")
+  fi
+fi
+if [[ -z "$count" ]]; then
+  if [[ -z "$TARGET_DB_PATH" ]]; then
+    echo "  ❌ retain-failed: TARGET_DB_PATH unset and no ADMIN_API_TOKEN — cannot probe"
+    fails=$((fails+1))
+  else
+    # TEST_PUBKEY is hex-validated → safe to inline single-quoted in SQL.
+    # Container/db path also validated; printf %q for defense in depth.
+    q="SELECT COUNT(*) FROM transmissions WHERE from_node = '$TEST_PUBKEY';"
+    qq=$(printf %q "$q")
+    if ! count=$(ssh_t "docker exec $(printf %q "$TARGET_CONTAINER") sqlite3 $(printf %q "$TARGET_DB_PATH") $qq" 2>/dev/null); then
+      count=$(ssh_t "sqlite3 $(printf %q "$TARGET_DB_PATH") $qq" 2>/dev/null || echo "")
+    fi
+  fi
+fi
+
+if [[ -z "$count" ]]; then
+  echo "  ❌ retain-failed: could not read transmissions count"
+  fails=$((fails+1))
+elif [[ "$count" =~ ^[0-9]+$ ]] && (( count > 0 )); then
+  echo "  ✅ DB retains $count packets from $TEST_PUBKEY"
+else
+  echo "  ❌ retain-failed: count=$count (expected > 0)"
+  fails=$((fails+1))
+fi
+
+echo "=== summary: $fails failure(s) before teardown ==="
+# trap handles teardown + exit
+exit "$fails"

scripts/migrate-fixture-hashes.go

@@ -0,0 +1,136 @@
+// migrate-fixture-hashes recomputes content hashes in a fixture DB using the
+// current ComputeContentHash formula.  Run once; idempotent.
+package main
+
+import (
+	"crypto/sha256"
+	"database/sql"
+	"encoding/hex"
+	"fmt"
+	"log"
+	"os"
+
+	_ "modernc.org/sqlite"
+)
+
+func computeContentHash(rawHex string) string {
+	buf, err := hex.DecodeString(rawHex)
+	if err != nil || len(buf) < 2 {
+		if len(rawHex) >= 16 {
+			return rawHex[:16]
+		}
+		return rawHex
+	}
+
+	headerByte := buf[0]
+	offset := 1
+	routeType := int(headerByte & 0x03)
+	if routeType == 2 || routeType == 3 { // transport
+		offset += 4
+	}
+	if offset >= len(buf) {
+		if len(rawHex) >= 16 {
+			return rawHex[:16]
+		}
+		return rawHex
+	}
+	pathByte := buf[offset]
+	offset++
+	hashSize := int((pathByte>>6)&0x3) + 1
+	hashCount := int(pathByte & 0x3F)
+	pathBytes := hashSize * hashCount
+
+	payloadStart := offset + pathBytes
+	if payloadStart > len(buf) {
+		if len(rawHex) >= 16 {
+			return rawHex[:16]
+		}
+		return rawHex
+	}
+
+	payload := buf[payloadStart:]
+	payloadType := (headerByte >> 2) & 0x0F
+	toHash := []byte{payloadType}
+
+	// TRACE = payload type 7
+	if int(payloadType) == 7 {
+		toHash = append(toHash, pathByte, 0x00)
+	}
+	toHash = append(toHash, payload...)
+
+	h := sha256.Sum256(toHash)
+	return hex.EncodeToString(h[:])[:16]
+}
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Fprintf(os.Stderr, "usage: %s <db-path>\n", os.Args[0])
+		os.Exit(1)
+	}
+	dbPath := os.Args[1]
+
+	db, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+
+	rows, err := db.Query("SELECT id, raw_hex, hash FROM transmissions")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	type update struct {
+		id      int
+		newHash string
+	}
+	var updates []update
+
+	for rows.Next() {
+		var id int
+		var rawHex, oldHash string
+		if err := rows.Scan(&id, &rawHex, &oldHash); err != nil {
+			log.Printf("scan: %v", err)
+			continue
+		}
+		newHash := computeContentHash(rawHex)
+		if newHash != oldHash {
+			updates = append(updates, update{id, newHash})
+		}
+	}
+	rows.Close()
+
+	if len(updates) == 0 {
+		fmt.Println("All hashes already match current formula.")
+		return
+	}
+
+	tx, err := db.Begin()
+	if err != nil {
+		log.Fatal(err)
+	}
+	stmt, err := tx.Prepare("UPDATE transmissions SET hash = ? WHERE id = ?")
+	if err != nil {
+		log.Fatal(err)
+	}
+	merged := 0
+	for _, u := range updates {
+		if _, err := stmt.Exec(u.newHash, u.id); err != nil {
+			// UNIQUE constraint = duplicate (same content, different old hash).
+			// Move observations to the surviving tx, then delete the dup.
+			log.Printf("update id %d: %v — merging duplicate", u.id, err)
+			// Find surviving tx id
+			var survID int
+			if err2 := tx.QueryRow("SELECT id FROM transmissions WHERE hash = ?", u.newHash).Scan(&survID); err2 == nil {
+				tx.Exec("UPDATE observations SET transmission_id = ? WHERE transmission_id = ?", survID, u.id)
+				tx.Exec("DELETE FROM transmissions WHERE id = ?", u.id)
+				merged++
+			}
+		}
+	}
+	stmt.Close()
+	if err := tx.Commit(); err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("Migrated %d hashes, merged %d duplicates.\n", len(updates)-merged, merged)
+}

test-channel-add-ux.js

@@ -0,0 +1,64 @@
+/**
+ * Tests for #759 — Add channel UX: button, hint, status feedback.
+ * Validates the HTML structure rendered by channels.js init.
+ */
+'use strict';
+
+const fs = require('fs');
+
+let passed = 0;
+let failed = 0;
+
+function assert(cond, msg) {
+  if (cond) { passed++; console.log('  ✓ ' + msg); }
+  else { failed++; console.error('  ✗ ' + msg); }
+}
+
+function assertIncludes(html, substr, msg) {
+  assert(html.includes(substr), msg);
+}
+
+// Read the channels.js source to extract the HTML template
+const src = fs.readFileSync(__dirname + '/public/channels.js', 'utf8');
+
+// Extract the sidebar HTML from the template literal
+const htmlMatch = src.match(/app\.innerHTML\s*=\s*`([\s\S]*?)`;/);
+const html = htmlMatch ? htmlMatch[1] : '';
+
+console.log('Test: Add channel UX (#759)');
+
+// 1. Button renders in the form
+assertIncludes(html, 'class="ch-add-btn"', 'Add button has ch-add-btn class');
+assertIncludes(html, 'type="submit"', 'Button is type=submit');
+assertIncludes(html, '>+</button>', 'Button shows + text');
+
+// 2. Form has proper structure
+assertIncludes(html, 'class="ch-add-form"', 'Form has ch-add-form class');
+assertIncludes(html, 'class="ch-add-row"', 'Row wrapper present');
+assert(!html.includes('class="ch-add-label"'), 'Label removed (redundant with hint)');
+
+// 3. Hint text present
+assertIncludes(html, 'class="ch-add-hint"', 'Hint div present');
+assertIncludes(html, 'e.g. #LongFast or 32-char hex key', 'Hint text correct');
+
+// 4. Status div present
+assertIncludes(html, 'id="chAddStatus"', 'Status div has correct id');
+assertIncludes(html, 'class="ch-add-status"', 'Status div has correct class');
+assertIncludes(html, 'style="display:none"', 'Status div hidden by default');
+
+// 5. showAddStatus function exists in source
+assert(src.includes('function showAddStatus('), 'showAddStatus function defined');
+assert(src.includes("'success'"), 'Success status type referenced');
+assert(src.includes("'error'"), 'Error status type referenced');
+
+// 6. CSS classes exist
+const css = fs.readFileSync(__dirname + '/public/style.css', 'utf8');
+assert(css.includes('.ch-add-form'), 'CSS: .ch-add-form defined');
+assert(css.includes('.ch-add-btn'), 'CSS: .ch-add-btn defined');
+assert(css.includes('.ch-add-hint'), 'CSS: .ch-add-hint defined');
+assert(css.includes('.ch-add-status'), 'CSS: .ch-add-status defined');
+assert(css.includes('.ch-add-row'), 'CSS: .ch-add-row defined');
+// .ch-add-label CSS kept for backward compat but label removed from HTML
+
+console.log('\n' + passed + ' passed, ' + failed + ' failed');
+process.exit(failed > 0 ? 1 : 0);

test-channel-decrypt-m345.js

@@ -0,0 +1,157 @@
+/**
+ * Tests for #725 M3 (PSK hex key), M4 (channel removal), M5 (message caching).
+ * Runs in Node.js via vm.createContext to simulate browser environment.
+ */
+'use strict';
+
+const vm = require('vm');
+const fs = require('fs');
+const { subtle } = require('crypto').webcrypto;
+
+let passed = 0;
+let failed = 0;
+
+function assert(cond, msg) {
+  if (cond) { passed++; console.log('  ✓ ' + msg); }
+  else { failed++; console.error('  ✗ ' + msg); }
+}
+
+// Build a minimal browser-like sandbox
+function createSandbox() {
+  const storage = {};
+  const localStorage = {
+    getItem: (k) => storage[k] !== undefined ? storage[k] : null,
+    setItem: (k, v) => { storage[k] = String(v); },
+    removeItem: (k) => { delete storage[k]; },
+    _data: storage
+  };
+
+  const ctx = {
+    window: {},
+    crypto: { subtle },
+    TextEncoder: TextEncoder,
+    TextDecoder: TextDecoder,
+    Uint8Array,
+    localStorage,
+    console,
+    Date,
+    JSON,
+    parseInt,
+    Math,
+    String,
+    Number,
+    Object,
+    Array,
+    RegExp,
+    Error,
+    Promise,
+    setTimeout,
+    btoa: (s) => Buffer.from(s, 'binary').toString('base64'),
+    atob: (s) => Buffer.from(s, 'base64').toString('binary'),
+  };
+  ctx.window = ctx;
+  ctx.self = ctx;
+  return ctx;
+}
+
+async function runTests() {
+  console.log('\n=== M3: PSK hex key detection ===');
+
+  // Load channel-decrypt.js in sandbox
+  const cdSrc = fs.readFileSync(__dirname + '/public/channel-decrypt.js', 'utf8');
+  const sandbox = createSandbox();
+  const context = vm.createContext(sandbox);
+  vm.runInContext(cdSrc, context);
+  const CD = sandbox.window.ChannelDecrypt;
+
+  // Test: isHexKey detection (via channels.js logic)
+  // We test the pattern directly since isHexKey is inside channels.js IIFE
+  const isHexKey = (val) => /^[0-9a-fA-F]{32}$/.test(val);
+
+  assert(isHexKey('0123456789abcdef0123456789abcdef'), 'Valid 32-char hex detected');
+  assert(isHexKey('AABBCCDD11223344AABBCCDD11223344'), 'Valid uppercase hex detected');
+  assert(!isHexKey('#LongFast'), 'Hashtag name NOT detected as hex');
+  assert(!isHexKey('0123456789abcdef'), 'Short hex (16 chars) NOT detected');
+  assert(!isHexKey('0123456789abcdef0123456789abcdefXX'), 'Too long NOT detected');
+  assert(!isHexKey('zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz'), 'Non-hex chars NOT detected');
+
+  // Test: PSK decrypt with known key bytes
+  console.log('\n=== M3: PSK decrypt produces correct plaintext ===');
+
+  // Derive a key from #LongFast for testing
+  const keyBytes = await CD.deriveKey('#LongFast');
+  assert(keyBytes.length === 16, 'Derived key is 16 bytes');
+
+  const keyHex = CD.bytesToHex(keyBytes);
+  assert(keyHex.length === 32, 'Key hex is 32 chars');
+
+  // Round-trip: hex → bytes → hex
+  const roundTrip = CD.bytesToHex(CD.hexToBytes(keyHex));
+  assert(roundTrip === keyHex, 'Hex round-trip preserves key');
+
+  // Channel hash computation works
+  const hashByte = await CD.computeChannelHash(keyBytes);
+  assert(typeof hashByte === 'number' && hashByte >= 0 && hashByte <= 255, 'Channel hash byte is valid (0-255)');
+
+  // PSK key (raw hex) stored and retrieved correctly
+  const pskHex = 'aabbccdd11223344aabbccdd11223344';
+  CD.storeKey('psk:aabbccdd', pskHex);
+  const keys = CD.getStoredKeys();
+  assert(keys['psk:aabbccdd'] === pskHex, 'PSK key stored and retrieved correctly');
+
+  console.log('\n=== M4: Channel removal clears key + cache ===');
+
+  // Store a key and some cached messages
+  CD.storeKey('#TestChannel', 'deadbeefdeadbeefdeadbeefdeadbeef');
+  CD.setCache('#TestChannel', [{ sender: 'A', text: 'hello', timestamp: '2026-01-01T00:00:00Z', packetHash: 'h1' }], '2026-01-01T00:00:00Z', 1);
+
+  // Verify they exist
+  var storedKeys = CD.getStoredKeys();
+  assert(storedKeys['#TestChannel'] === 'deadbeefdeadbeefdeadbeefdeadbeef', 'Key exists before removal');
+  var cachedBefore = CD.getCache('#TestChannel');
+  assert(cachedBefore && cachedBefore.messages.length === 1, 'Cache exists before removal');
+
+  // Remove the key (also clears cache)
+  CD.removeKey('#TestChannel');
+  var storedAfter = CD.getStoredKeys();
+  assert(!storedAfter['#TestChannel'], 'Key cleared after removal');
+  var cachedAfter = CD.getCache('#TestChannel');
+  assert(!cachedAfter, 'Cache cleared after removal');
+
+  console.log('\n=== M5: Cache operations ===');
+
+  // Test: setCache with count and size limit
+  var bigMessages = [];
+  for (var i = 0; i < 1200; i++) {
+    bigMessages.push({ sender: 'S', text: 'msg' + i, timestamp: '2026-01-01T00:00:' + String(i).padStart(2, '0') + 'Z', packetHash: 'h' + i });
+  }
+  CD.setCache('bigchannel', bigMessages, '2026-01-01T00:20:00Z', 1200);
+  var bigCached = CD.getCache('bigchannel');
+  assert(bigCached.messages.length <= 1000, 'Cache enforces 1000 message limit (got ' + bigCached.messages.length + ')');
+  assert(bigCached.count === 1200, 'Cache stores total count');
+  assert(bigCached.lastTimestamp === '2026-01-01T00:20:00Z', 'Cache stores lastTimestamp');
+  // Should keep most recent 1000
+  assert(bigCached.messages[0].packetHash === 'h200', 'Cache keeps most recent 1000 (first is h200)');
+
+  // Test: cache hit (delta fetch scenario)
+  CD.setCache('deltatest', [
+    { sender: 'A', text: 'old', timestamp: '2026-01-01T00:00:00Z', packetHash: 'p1' }
+  ], '2026-01-01T00:00:00Z', 1);
+
+  var deltaCache = CD.getCache('deltatest');
+  assert(deltaCache.messages.length === 1, 'Delta cache has 1 message');
+  assert(deltaCache.lastTimestamp === '2026-01-01T00:00:00Z', 'Delta cache lastTimestamp correct');
+  assert(deltaCache.count === 1, 'Delta cache count correct');
+
+  // Test: clearChannelCache
+  CD.setCache('clearthis', [{ sender: 'X', text: 'y' }], 'ts', 1);
+  assert(CD.getCache('clearthis') !== null, 'Cache exists before clear');
+  CD.clearChannelCache('clearthis');
+  assert(CD.getCache('clearthis') === null, 'Cache cleared by clearChannelCache');
+
+  console.log('\n=== Results ===');
+  console.log('Passed: ' + passed + ', Failed: ' + failed);
+  process.exit(failed > 0 ? 1 : 0);
+}
+
+runTests().catch(e => { console.error(e); process.exit(1); });

test-e2e-playwright.js

@@ -231,6 +231,30 @@ async function run() {
     assert(hasStatus, 'No status indicator found in node detail');
   });
 
+  // Test: Node side panel Details link navigates to full detail page (#778)
+  await test('Node side panel Details link navigates', async () => {
+    await page.goto(`${BASE}/#/nodes`, { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('table tbody tr');
+    // Click first row to open side panel
+    const firstRow = await page.$('table tbody tr');
+    assert(firstRow, 'No node rows found');
+    await firstRow.click();
+    await page.waitForSelector('.node-detail');
+    // Find the Details link in the side panel
+    const detailsLink = await page.$('#nodesRight a.btn-primary[href^="#/nodes/"]');
+    assert(detailsLink, 'Details link not found in side panel');
+    const href = await detailsLink.getAttribute('href');
+    // Click the Details link — this should navigate to the full detail page
+    await detailsLink.click();
+    // Wait for navigation — the full detail page has sections like neighbors/packets
+    await page.waitForFunction((expectedHash) => {
+      return location.hash === expectedHash;
+    }, href, { timeout: 5000 });
+    // Verify we're on the full detail page (should have section tabs or detail content)
+    const hash = await page.evaluate(() => location.hash);
+    assert(hash === href, `Expected hash "${href}" but got "${hash}"`);
+  });
+
   // Test: Nodes page has WebSocket auto-update listener (#131)
   await test('Nodes page has WebSocket auto-update', async () => {
     await page.goto(`${BASE}/#/nodes`, { waitUntil: 'domcontentloaded' });
@@ -398,8 +422,13 @@ async function run() {
       }
     }, { timeout: 10000 });
 
-    // Full reload on the packets page — scripts re-execute, IIFE reads localStorage
-    await page.reload({ waitUntil: 'load' });
+    // Force a full page reload to reset module-level state (savedTimeWindowMin is
+    // read from localStorage once at IIFE time). Navigating from /#/packets to /#/packets
+    // is a hash-only change — no reload, so the IIFE never re-reads localStorage.
+    // Going to / first forces a fresh page load, then the hash change to /#/packets
+    // calls init() with the freshly-read savedTimeWindowMin = 60.
+    await page.goto(`${BASE}/`, { waitUntil: 'load' });
+    await page.goto(`${BASE}/#/packets`, { waitUntil: 'load' });
     await page.waitForSelector('#fTimeWindow', { timeout: 10000 });
     const timeWindowValue = await page.$eval('#fTimeWindow', (el) => el.value);
     assert(timeWindowValue === '60', `Expected time window dropdown to restore 60, got ${timeWindowValue}`);
@@ -1470,13 +1499,18 @@ async function run() {
   // ─── Neighbor section tests ───────────────────────────────────────────────
 
   await test('Node detail: neighbors section exists with correct columns', async () => {
+    // Full-screen node view (with #node-neighbors) is mobile-only since #676 fix.
+    await page.setViewportSize({ width: 390, height: 844 });
     // Navigate to a node detail page (use the first node in the list)
     await page.goto(BASE + '/#/nodes');
     await page.waitForSelector('#nodesBody tr[data-key]', { timeout: 10000 });
     // Get the first node's pubkey from the row's data-key attribute
     const pubkey = await page.$eval('#nodesBody tr[data-key]', el => el.dataset.key);
-    await page.goto(BASE + '/#/nodes/' + pubkey);
-    await page.waitForSelector('#node-neighbors', { timeout: 10000 });
+    // Use evaluate to change hash (reliable same-document navigation)
+    await page.evaluate((pk) => { location.hash = '#/nodes/' + pk; }, pubkey);
+    // Wait for the full-node view to render (async API fetch populates body)
+    await page.waitForSelector('.node-fullscreen', { timeout: 10000 });
+    await page.waitForSelector('#node-neighbors', { timeout: 25000 });
     // Check the section exists
     const header = await page.$eval('#fullNeighborsHeader', el => el.textContent);
     assert(header.startsWith('Neighbors'), 'Header should start with "Neighbors", got: ' + header);
@@ -1500,6 +1534,7 @@ async function run() {
       const text = await page.$eval('#fullNeighborsContent', el => el.textContent);
       assert(text.includes('No neighbor data') || text.includes('Could not load'), 'Should show empty or error state');
     }
+    await page.setViewportSize({ width: 1280, height: 800 });
   });
 
 
@@ -1653,6 +1688,33 @@ async function run() {
     assert(url.includes('tab=room'), `URL should contain tab=room after click, got: ${url}`);
   });
 
+  // Test: clicking a node on desktop updates URL hash (#676)
+  await test('Desktop: clicking a node updates URL to #/nodes/{pubkey}', async () => {
+    await page.setViewportSize({ width: 1280, height: 800 });
+    await page.goto(BASE + '#/nodes', { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#nodesBody tr[data-key]', { timeout: 10000 });
+    const pubkey = await page.$eval('#nodesBody tr[data-key]', el => el.dataset.key);
+    await page.click('#nodesBody tr[data-key]');
+    await page.waitForTimeout(300);
+    const url = page.url();
+    assert(url.includes(encodeURIComponent(pubkey)), `URL should contain pubkey after click, got: ${url}`);
+    assert(!url.includes('node-fullscreen') || await page.$('#nodesRight:not(.empty)'), 'Split panel should be visible on desktop');
+  });
+
+  // Test: loading #/nodes/{pubkey} on desktop opens full-screen detail view (#823)
+  // Updated from #676's earlier "split panel on desktop" assertion. The Details
+  // link now opens the full-screen single-node view on desktop too — see PR #824.
+  await test('Desktop: deep link #/nodes/{pubkey} opens full-screen detail view', async () => {
+    await page.setViewportSize({ width: 1280, height: 800 });
+    await page.goto(BASE + '#/nodes', { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#nodesBody tr[data-key]', { timeout: 10000 });
+    const pubkey = await page.$eval('#nodesBody tr[data-key]', el => el.dataset.key);
+    await page.goto(BASE + '#/nodes/' + encodeURIComponent(pubkey), { waitUntil: 'domcontentloaded' });
+    await page.waitForTimeout(500);
+    const hasFullScreen = await page.$('.node-fullscreen');
+    assert(hasFullScreen, 'Full-screen detail view should be open on desktop deep link (#823)');
+  });
+
   // Test: packets timeWindow deep link
   await test('Packets timeWindow deep link restores dropdown', async () => {
     await page.goto(BASE + '#/packets?timeWindow=60', { waitUntil: 'domcontentloaded' });
@@ -1663,6 +1725,36 @@ async function run() {
     assert(url.includes('timeWindow=60'), `URL should still contain timeWindow=60, got: ${url}`);
   });
 
+  // Test: hash filter updates URL and is restored (#682)
+  await test('Packets hash filter updates URL and restores on reload', async () => {
+    await page.goto(BASE + '#/packets', { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#fHash', { timeout: 8000 });
+    await page.fill('#fHash', 'abc123');
+    await page.waitForTimeout(500);
+    const url = page.url();
+    assert(url.includes('hash=abc123'), `URL should contain hash=abc123, got: ${url}`);
+    // Reload and check input restored
+    await page.goto(url, { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#fHash', { timeout: 8000 });
+    const val = await page.$eval('#fHash', el => el.value);
+    assert(val === 'abc123', `fHash should be restored to abc123, got: ${val}`);
+  });
+
+  // Test: Wireshark filter expression updates URL and is restored (#682)
+  await test('Packets filter expression updates URL and restores on reload', async () => {
+    await page.goto(BASE + '#/packets', { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#packetFilterInput', { timeout: 8000 });
+    await page.fill('#packetFilterInput', 'type == ADVERT');
+    await page.waitForTimeout(500);
+    const url = page.url();
+    assert(url.includes('filter=') && url.includes('ADVERT'), `URL should contain filter=type%3D%3DADVERT, got: ${url}`);
+    // Reload and check expression restored
+    await page.goto(url, { waitUntil: 'domcontentloaded' });
+    await page.waitForSelector('#packetFilterInput', { timeout: 8000 });
+    const val = await page.$eval('#packetFilterInput', el => el.value);
+    assert(val === 'type == ADVERT', `packetFilterInput should be restored, got: ${val}`);
+  });
+
   // Test: timeWindow change updates URL
   await test('Packets timeWindow change updates URL', async () => {
     await page.goto(BASE + '#/packets', { waitUntil: 'domcontentloaded' });