diff --git a/tests/Makefile.am b/tests/Makefile.am
index a6c64451..7e12f999 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -550,9 +550,10 @@ test_chat_sync_stress_SOURCES = test_chat_sync_stress.c
 test_chat_sync_stress_CFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/lib
 test_chat_sync_stress_LDADD = $(LIBUTUN) $(CRYPTO_LIBS) $(COMMON_LIBS)
 
-test_chat_join_SOURCES = test_chat_join.c
+test_chat_join_SOURCES = test_chat_join.c $(test_clock_sources)
 test_chat_join_CFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/src/chat -I$(top_srcdir)/src/routing_layer -I$(top_srcdir)/src/transport_layer -I$(top_srcdir)/lib
 test_chat_join_LDADD = $(LIBUTUN) $(CRYPTO_LIBS) $(COMMON_LIBS)
+test_chat_join_LDFLAGS = $(test_clock_ldflags)
 
 test_chat_join_e2e_SOURCES = test_chat_join_e2e.c
 test_chat_join_e2e_CFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/src/chat -I$(top_srcdir)/src/routing_layer -I$(top_srcdir)/src/transport_layer -I$(top_srcdir)/lib
diff --git a/tests/test_chat_join.c b/tests/test_chat_join.c
index 5f9d4f70..94d5c017 100644
--- a/tests/test_chat_join.c
+++ b/tests/test_chat_join.c
@@ -27,6 +27,7 @@
 #include "../lib/debug_config.h"
 #include "../lib/mem.h"
 #include "test_utils.h"
+#include "test_clock.h"
 
 #include <sqlite3.h>
 #define OPENSSL_API_COMPAT 0x10100000L
@@ -343,7 +344,8 @@ static void destroy_instances(int n) {
 static int wait_connected(int n) {
     if (n <= 1) return 1;
     int need = n * (n - 1);
-    for (int a = 0; a < 2000; a++) {
+    uint64_t deadline = get_time_tb() + 20000;
+    while (get_time_tb() < deadline) {
         int ok = 0;
         for (int i = 0; i < n; i++) {
             struct ll_entry* e = g_inst[i]->connections->head;
@@ -358,13 +360,15 @@ static int wait_connected(int n) {
             }
         }
         if (ok >= need) return 1;
-        uasync_poll(g_ua, POLL_MS);
+        test_clock_poll(g_ua, POLL_MS);
     }
+    DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "JOIN test: connection timeout nodes=%d required_links=%d budget_ms=2000", n, need);
     return 0;
 }
 
 static int wait_chat_bgp(int n) {
-    for (int a = 0; a < 8000; a++) {
+    uint64_t deadline = get_time_tb() + 80000;
+    while (get_time_tb() < deadline) {
         int ok = 1;
         for (int i = 0; i < n && ok; i++) {
             struct TOPO_GROUP* g = topo_groups_find(g_inst[i]->topo_groups, g_group_id);
@@ -376,8 +380,10 @@ static int wait_chat_bgp(int n) {
             }
         }
         if (ok) return 1;
-        uasync_poll(g_ua, POLL_MS);
+        test_clock_poll(g_ua, POLL_MS);
     }
+    DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "JOIN test: group routes timeout nodes=%d group=%llu budget_ms=8000",
+                n, (unsigned long long)g_group_id);
     return 0;
 }
 
@@ -488,23 +494,37 @@ static void t_validate_pubkey(void) {
     }
 }
 
-struct registration_result { int calls, result; };
+struct registration_result { int calls, result; uint64_t fired_tb; };
 static void registered(void* arg, int result) {
     struct registration_result* r = arg;
-    r->calls++; r->result = result;
+    r->calls++; r->result = result; r->fired_tb = get_time_tb();
 }
 
 static void poll_ms(int ms) {
-    uint64_t until = get_time_tb() + (uint64_t)ms * 10;
-    while (get_time_tb() < until) uasync_poll(g_ua, POLL_MS);
+    test_clock_run_for(g_ua, ms * 10);
 }
 
 static int wait_registered(struct registration_result* r) {
     uint64_t until = get_time_tb() + JOIN_REGISTER_TIMEOUT_TB + 10000;
-    while (!r->calls && get_time_tb() < until) uasync_poll(g_ua, POLL_MS);
+    while (!r->calls && get_time_tb() < until) test_clock_poll(g_ua, POLL_MS);
     return r->calls == 1 && r->result == CHAT_JOIN_OK;
 }
 
+/* Убеждаемся, что регистрация жива до срока; затем настоящий таймер выдаёт ровно один TIMEOUT. */
+static int wait_registration_timeout(struct registration_result* r, uint64_t started) {
+    uint64_t before = started + JOIN_REGISTER_TIMEOUT_TB - 1000, now = get_time_tb();
+    if (now < before) test_clock_run_for(g_ua, (int)(before - now));
+    int pending = !r->calls && g_inst[0]->join_registrations != NULL;
+    wait_registered(r);
+    int ok = pending && r->calls == 1 && r->result == CHAT_JOIN_TIMEOUT && r->fired_tb + 10 >= started + JOIN_REGISTER_TIMEOUT_TB;
+    if (!ok) DEBUG_ERROR(DEBUG_CATEGORY_DEBUG, "JOIN timeout failed: pending=%d calls=%d result=%d fired_tb=%llu started_tb=%llu budget_tb=%d",
+                         pending, r->calls, r->result, (unsigned long long)r->fired_tb,
+                         (unsigned long long)started, JOIN_REGISTER_TIMEOUT_TB);
+    else DEBUG_INFO(DEBUG_CATEGORY_DEBUG, "JOIN timeout: pending before deadline; one TIMEOUT elapsed_tb=%llu budget_tb=%d",
+                    (unsigned long long)(r->fired_tb - started), JOIN_REGISTER_TIMEOUT_TB);
+    return ok;
+}
+
 static etcp_recv_fn original_join_recv;
 static struct ll_entry* held_ack;
 static struct ETCP_CONN* held_conn;
@@ -573,11 +593,12 @@ static void t_registration_edges(void) {
     TEST("registration: missing ACK times out once, late ACK ignored"); {
         struct registration_result r = {0};
         uint64_t key = JOIN_KEY + 12;
+        uint64_t started = get_time_tb();
         struct chat_join_registration* req = chat_join_register_key(g_inst[0], g_group_id, g_nid[1], key, registered, &r);
-        wait_registered(&r);
+        int timed_out = wait_registration_timeout(&r, started);
         int had_ack = held_ack != NULL;
         release_ack(); poll_ms(20);
-        if (req && had_ack && r.calls == 1 && r.result == CHAT_JOIN_TIMEOUT && !g_inst[0]->join_registrations
+        if (req && had_ack && timed_out && r.calls == 1 && r.result == CHAT_JOIN_TIMEOUT && !g_inst[0]->join_registrations
             && !chat_join_lookup_inviter(g_inst[0], g_group_id, key)) OK(); else FAIL();
         if (!r.calls && req) chat_join_cancel_registration(req);
     }
@@ -637,11 +658,12 @@ static void t_registration_edges(void) {
     }
     TEST("registration: connection node shutdown times out without success"); {
         struct registration_result r = {0};
+        uint64_t started = get_time_tb();
         struct chat_join_registration* req = chat_join_register_key(g_inst[0], g_group_id, g_nid[1], JOIN_KEY + 27, registered, &r);
         chat_join_destroy(g_inst[1]); member_sync_destroy(g_inst[1]);
         g_inst[1]->running = 0; utun_instance_destroy(g_inst[1]); g_inst[1] = NULL;
-        wait_registered(&r);
-        if (req && r.calls == 1 && r.result == CHAT_JOIN_TIMEOUT && !g_inst[0]->join_registrations
+        int timed_out = wait_registration_timeout(&r, started);
+        if (req && timed_out && r.calls == 1 && r.result == CHAT_JOIN_TIMEOUT && !g_inst[0]->join_registrations
             && !chat_join_lookup_inviter(g_inst[0], g_group_id, JOIN_KEY + 27)) OK(); else FAIL();
         if (!r.calls && req) chat_join_cancel_registration(req);
     }
@@ -704,6 +726,7 @@ static void t_integration(void) {
 
 int main(void) {
     debug_config_init(); debug_set_level(DEBUG_LEVEL_ERROR);
+    test_clock_init(1000);
     if (getenv("UTUN_TEST_DEBUG")) {
         debug_set_category_level_by_name("chat_sync", "info");
         debug_set_category_level_by_name("member_sync", "info");
@@ -748,5 +771,6 @@ int main(void) {
         uasync_destroy(g_ua, 0); g_ua = NULL;
     }
     t_rmdir(g_tdir);
+    test_clock_finish();
     return G_FAILED > 0 ? 1 : 0;
 }