diff --git a/cmd/server/routes.go b/cmd/server/routes.go
index 8844107..b1c84c8 100644
--- a/cmd/server/routes.go
+++ b/cmd/server/routes.go
@@ -425,7 +425,7 @@ func (s *Server) handlePerf(w http.ResponseWriter, r *http.Request) {
 		sorted := sortedCopy(ep.Recent)
 		d := &EndpointStatsResp{
 			Count: ep.Count,
-			AvgMs: round(ep.TotalMs/float64(ep.Count), 1),
+			AvgMs: safeAvg(ep.TotalMs, float64(ep.Count)),
 			P50Ms: round(percentile(sorted, 0.5), 1),
 			P95Ms: round(percentile(sorted, 0.95), 1),
 			MaxMs: round(ep.MaxMs, 1),
diff --git a/cmd/server/routes_test.go b/cmd/server/routes_test.go
index 5676d91..8daa3e0 100644
--- a/cmd/server/routes_test.go
+++ b/cmd/server/routes_test.go
@@ -397,7 +397,7 @@ func TestPerfEndpoint(t *testing.T) {
 	if !ok {
 		t.Fatal("expected goRuntime object in perf response")
 	}
-	for _, field := range []string{"heapMB", "sysMB", "numGoroutine", "numGC", "gcPauseMs"} {
+	for _, field := range []string{"goroutines", "numGC", "pauseTotalMs", "lastPauseMs", "heapAllocMB", "heapSysMB", "heapInuseMB", "heapIdleMB", "numCPU"} {
 		if _, ok := goRuntime[field]; !ok {
 			t.Errorf("expected %s in goRuntime", field)
 		}
diff --git a/cmd/server/testdata/golden/shapes.json b/cmd/server/testdata/golden/shapes.json
index ade0f69..d04e74e 100644
--- a/cmd/server/testdata/golden/shapes.json
+++ b/cmd/server/testdata/golden/shapes.json
@@ -168,13 +168,18 @@
         "type": "array",
         "elementShape": {
           "type": "object",
-          "dynamicKeys": true,
-          "valueShape": {
-            "type": "number"
-          },
-          "requiredKeys": {
+          "keys": {
             "hour": {
               "type": "string"
+            },
+            "1": {
+              "type": "number"
+            },
+            "2": {
+              "type": "number"
+            },
+            "3": {
+              "type": "number"
             }
           }
         }
@@ -1483,19 +1488,31 @@
       "goRuntime": {
         "type": "object",
         "keys": {
-          "heapMB": {
-            "type": "number"
-          },
-          "sysMB": {
-            "type": "number"
-          },
-          "numGoroutine": {
+          "goroutines": {
             "type": "number"
           },
           "numGC": {
             "type": "number"
           },
-          "gcPauseMs": {
+          "pauseTotalMs": {
+            "type": "number"
+          },
+          "lastPauseMs": {
+            "type": "number"
+          },
+          "heapAllocMB": {
+            "type": "number"
+          },
+          "heapSysMB": {
+            "type": "number"
+          },
+          "heapInuseMB": {
+            "type": "number"
+          },
+          "heapIdleMB": {
+            "type": "number"
+          },
+          "numCPU": {
             "type": "number"
           }
         }
diff --git a/cmd/server/websocket_test.go b/cmd/server/websocket_test.go
index 5e63beb..0ae6988 100644
--- a/cmd/server/websocket_test.go
+++ b/cmd/server/websocket_test.go
@@ -179,8 +179,8 @@ func TestBroadcastFullBuffer(t *testing.T) {
 func TestBroadcastMarshalError(t *testing.T) {
 	hub := NewHub()
 
-	// Marshal error: channels can't be marshaled
-	hub.Broadcast(make(chan int))
+	// Marshal error: functions can't be marshaled to JSON
+	hub.Broadcast(map[string]interface{}{"bad": func() {}})
 	// Should not panic — just log and return
 }