diff --git a/CMakeLists.txt b/CMakeLists.txt
index a41bd5e81..83a0a0ce1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -163,6 +163,9 @@ pkg_use_module(LIBCONFIG            libconfig     )
 # For auto tests.
 pkg_use_module(CHECK                check         )
 
+# For tox-spectest.
+pkg_use_module(MSGPACK              msgpack       )
+
 # For av_test.
 pkg_use_module(OPENCV               opencv        )
 pkg_use_module(PORTAUDIO            portaudio-2.0 )
@@ -337,6 +340,31 @@ add_module(toxencryptsave
   toxencryptsave/toxencryptsave.c)
 target_link_modules(toxencryptsave toxcore)
 
+################################################################################
+#
+# :: Tox specification tests
+#
+################################################################################
+
+find_program(SPECTEST NAMES
+  tox-spectest
+  ${CMAKE_SOURCE_DIR}/../.cabal-sandbox/bin/tox-spectest)
+
+if(SPECTEST AND MSGPACK_FOUND)
+  add_c_executable(toxcore-sut
+    testing/hstox/binary_decode.c
+    testing/hstox/binary_encode.c
+    testing/hstox/driver.c
+    testing/hstox/methods.c
+    testing/hstox/packet_kinds.c
+    testing/hstox/test_main.c
+    testing/hstox/util.c)
+  target_link_modules(toxcore-sut
+    toxcore
+    ${MSGPACK_LIBRARIES})
+  add_test(NAME spectest COMMAND ${SPECTEST} $<TARGET_FILE:toxcore-sut>)
+endif()
+
 ################################################################################
 #
 # :: Automated regression tests
diff --git a/testing/hstox/binary_decode.c b/testing/hstox/binary_decode.c
index aa4d79353..f43bae64b 100644
--- a/testing/hstox/binary_decode.c
+++ b/testing/hstox/binary_decode.c
@@ -3,7 +3,7 @@
 #include "byteswap.h"
 #include "packet_kinds.h"
 
-#include <DHT.h>
+#include "../../toxcore/DHT.h"
 
 METHOD(bin, Binary_decode, CipherText)
 {
diff --git a/testing/hstox/binary_encode.c b/testing/hstox/binary_encode.c
index a39533c01..9b9d38760 100644
--- a/testing/hstox/binary_encode.c
+++ b/testing/hstox/binary_encode.c
@@ -3,7 +3,7 @@
 #include "byteswap.h"
 #include "packet_kinds.h"
 
-#include <DHT.h>
+#include "../../toxcore/DHT.h"
 
 METHOD(bin, Binary_encode, CipherText)
 {
diff --git a/testing/hstox/driver.c b/testing/hstox/driver.c
index 817731904..7a9a907e8 100644
--- a/testing/hstox/driver.c
+++ b/testing/hstox/driver.c
@@ -17,7 +17,7 @@
 
 #include <sodium.h>
 
-static void handle_interrupt(int signum)
+static void __attribute__((__noreturn__)) handle_interrupt(int signum)
 {
     printf("Caught signal %d; exiting cleanly.\n", signum);
     exit(0);
diff --git a/testing/hstox/methods.c b/testing/hstox/methods.c
index 08ad50fa0..a025acc4c 100644
--- a/testing/hstox/methods.c
+++ b/testing/hstox/methods.c
@@ -2,8 +2,8 @@
 
 #include "util.h"
 
-#include <crypto_core.h>
-#include <net_crypto.h>
+#include "../../toxcore/crypto_core.h"
+#include "../../toxcore/net_crypto.h"
 
 char const *const failure       = "Failure";
 char const *const pending       = "Pending";
diff --git a/testing/hstox/packet_kinds.c b/testing/hstox/packet_kinds.c
index 314c814b4..aa0d2f267 100644
--- a/testing/hstox/packet_kinds.c
+++ b/testing/hstox/packet_kinds.c
@@ -1,6 +1,6 @@
 #include "packet_kinds.h"
 
-#include <network.h>
+#include "../../toxcore/network.h"
 
 uint8_t const packet_kinds[21] = {
     // = PingRequest       -- 0x00: Ping request