diff --git a/.gitignore b/.gitignore
index faca4151..1d724f9c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,7 +11,8 @@ tools/chatgui/ffmpeg/ffmpeg_build/
 *.a
 *.so
 *.so.*
-utun
+/utun
+/src/utun
 test_serialize
 linux-x64-deb
 
diff --git a/src/chat/chat_setting.c b/src/chat/chat_setting.c
index 4f37f166..d542364d 100644
--- a/src/chat/chat_setting.c
+++ b/src/chat/chat_setting.c
@@ -47,6 +47,9 @@ static const struct chat_setting_def g_setting_defs[] = {
     {"compressor_max_gain_db",      CHAT_SETTING_INT,  25,  1, 100},
     {"compressor_rise_rate",        CHAT_SETTING_INT,  10,  1, 100},
     {"media_download_max_peers",    CHAT_SETTING_INT,  3,   1, 16},
+    {"standby_active_sec",         CHAT_SETTING_INT,  2,   1, 3600},
+    {"standby_sleep_sec",          CHAT_SETTING_INT,  60,  1, 86400},
+    {"standby_min_sleep_sec",      CHAT_SETTING_INT,  15,  1, 86400},
     {"join_policy",                CHAT_SETTING_INT,  1,   0, 2},  /* 0=autojoin, 1=ask, 2=deny */
     {"whisper_enabled",            CHAT_SETTING_BOOL, 0,   0, 1},
     {"whisper_model_path",         CHAT_SETTING_STRING, 0, 0, 0},
diff --git a/src/routing_layer/conn_mgr_core.c b/src/routing_layer/conn_mgr_core.c
index 5dc6be87..72986340 100644
--- a/src/routing_layer/conn_mgr_core.c
+++ b/src/routing_layer/conn_mgr_core.c
@@ -24,6 +24,9 @@
 #include "../transport_layer/etcp_connect.h"
 #include "route_ping.h"
 #include "../chat/chat_core.h"
+#ifdef UTUN_HAVE_STANDBY
+#include "standby.h"
+#endif
 
 /* ═══════ forward-декларации ═══════ */
 
@@ -326,6 +329,10 @@ void conn_mgr_destroy(struct CONN_MGR* mgr) {
     DEBUG_INFO(DEBUG_CATEGORY_SYS, "[CM_DESTROY] 1 bg_ping done");
     if (mgr->candidate_ping_timer) { uasync_cancel_timeout(mgr->instance->ua, mgr->candidate_ping_timer); mgr->candidate_ping_timer = NULL; }
     DEBUG_INFO(DEBUG_CATEGORY_SYS, "[CM_DESTROY] 2 cand_ping done");
+#ifdef UTUN_HAVE_STANDBY
+    if (mgr->bg_ping_wait) { standby_wait_cancel(mgr->bg_ping_wait); mgr->bg_ping_wait = NULL; }
+    if (mgr->candidate_ping_wait) { standby_wait_cancel(mgr->candidate_ping_wait); mgr->candidate_ping_wait = NULL; }
+#endif
     {   size_t ec = queue_entry_count(mgr->entries);
         DEBUG_INFO(DEBUG_CATEGORY_SYS, "[CM_DESTROY] 3 entries count=%zu", ec);
         struct ll_entry* e = mgr->entries->head;
diff --git a/src/routing_layer/conn_mgr_monitor.c b/src/routing_layer/conn_mgr_monitor.c
index 6818a264..99e77fac 100644
--- a/src/routing_layer/conn_mgr_monitor.c
+++ b/src/routing_layer/conn_mgr_monitor.c
@@ -13,6 +13,9 @@
 #include "topo_group.h"
 #include "route_connectivity.h"
 #include "route_ping.h"
+#ifdef UTUN_HAVE_STANDBY
+#include "standby.h"
+#endif
 
 /* ═══════ probe time утилиты ═══════ */
 
@@ -104,6 +107,13 @@ static void cm_bg_ping_to_node(struct CONN_MGR* mgr, struct TOPO_NODE* ni) {
  * и INDIRECT-фаза не может выбрать посредника. */
 void cm_bg_ping_timer_cb(void* arg) {
     struct CONN_MGR* mgr = (struct CONN_MGR*)arg;
+#ifdef UTUN_HAVE_STANDBY
+    if (standby_get_sleep_tb() > 0) {
+        mgr->bg_ping_wait = standby_wait(mgr, cm_bg_ping_timer_cb);
+        return;
+    }
+    mgr->bg_ping_wait = NULL;
+#endif
     struct TOPO_GROUP* group = mgr->group;
     if (!group || !group->nodes) goto rearm;
     size_t total = queue_entry_count(group->nodes);
@@ -150,6 +160,13 @@ static int cm_has_active_conn(struct TOPO_GROUP* g, uint64_t nid) {
  * Вызывается раз в ~2с, самоперезапускается. */
 void cm_candidate_ping_timer_cb(void* arg) {
     struct CONN_MGR* mgr = (struct CONN_MGR*)arg; uint64_t now = get_time_tb();
+#ifdef UTUN_HAVE_STANDBY
+    if (standby_get_sleep_tb() > 0) {
+        mgr->candidate_ping_wait = standby_wait(mgr, cm_candidate_ping_timer_cb);
+        return;
+    }
+    mgr->candidate_ping_wait = NULL;
+#endif
     for (uint8_t i = 0; i < mgr->best_candidate_count; i++) {
         uint64_t nid = mgr->best_candidates[i].node_id;
         struct TOPO_GROUP_NODE* nq = topo_node_find_by_id(mgr->group, nid);
diff --git a/src/routing_layer/conn_mgr_priv.h b/src/routing_layer/conn_mgr_priv.h
index 4e5ea4e1..03cb5717 100644
--- a/src/routing_layer/conn_mgr_priv.h
+++ b/src/routing_layer/conn_mgr_priv.h
@@ -164,6 +164,7 @@ struct CONN_MGR {
     struct UTUN_INSTANCE* instance; struct TOPO_GROUP* group;
     struct ll_queue* entries;
     void *bg_ping_timer, *candidate_ping_timer;
+    void *bg_ping_wait, *candidate_ping_wait;  /* standby_wait handle (Android) */
     size_t bg_ping_cursor; uint64_t bg_ping_cycle_start_tb;
     struct CONN_MGR_CANDIDATE best_candidates[CONN_MGR_MAX_CANDIDATES]; uint8_t best_candidate_count;
     uint32_t next_request_id, direct_timeout_ms; uint8_t initialized;
diff --git a/src/routing_layer/route_connectivity.c b/src/routing_layer/route_connectivity.c
index ff1c6e80..4d22c9db 100644
--- a/src/routing_layer/route_connectivity.c
+++ b/src/routing_layer/route_connectivity.c
@@ -17,6 +17,9 @@
 #include "topo_group.h"
 #include "route_connectivity.h"
 #include "topo_node_sqlite.h"
+#ifdef UTUN_HAVE_STANDBY
+#include "standby.h"
+#endif
 
 #define CONN_MAX_SOCKET_CANDIDATES 8
 
@@ -293,11 +296,46 @@ static void conn_probe_finish(struct conn_probe_ctx* ctx, int ok) {
 
 // ---- public API ----
 
+#ifdef UTUN_HAVE_STANDBY
+/* Контекст пробы, отложенной до следующего активного интервала (standby_wait). */
+struct route_probe_defer {
+    struct UTUN_INSTANCE* instance;
+    struct TOPO_GROUP* group;
+    struct TOPO_GROUP_NODE* nq;
+    void* wait_handle;                 /* handle standby_wait для отмены */
+};
+
+static void route_connectivity_probe_deferred_cb(void* arg) {
+    struct route_probe_defer* d = (struct route_probe_defer*)arg;
+    struct TOPO_GROUP_NODE* nq = d->nq;
+    nq->connectivity.probe_deferred_wait = NULL;
+    nq->connectivity.probe_status = PROBE_STATUS_NONE;
+    route_connectivity_probe_node(d->instance, d->group, nq);
+    u_free(d);
+}
+#endif
+
 void route_connectivity_probe_node(struct UTUN_INSTANCE* instance, struct TOPO_GROUP* group, struct TOPO_GROUP_NODE* nq) {
     if (!instance || !nq) return;
     struct TOPO_NODE* ni = topo_node_registry_find(instance->topo_groups, nq->node_id);
     if (!ni) return;
     if (nq->node_id == instance->node_id) return; // не пингуем себя
+#ifdef UTUN_HAVE_STANDBY
+    if (nq->connectivity.probe_status == PROBE_STATUS_DEFERRED) {
+        DEBUG_INFO(DEBUG_CATEGORY_BGP, "probe already deferred for node %016llx", (unsigned long long)nq->node_id);
+        return;
+    }
+    if (standby_get_sleep_tb() > 0) {
+        nq->connectivity.probe_status = PROBE_STATUS_DEFERRED;
+        struct route_probe_defer* d = u_calloc(1, sizeof(*d));
+        if (!d) { nq->connectivity.probe_status = PROBE_STATUS_NONE; return; }
+        d->instance = instance; d->group = group; d->nq = nq;
+        void* h = standby_wait(d, route_connectivity_probe_deferred_cb);
+        if (h) { d->wait_handle = h; nq->connectivity.probe_deferred_wait = d; }
+        /* else: cb вызван синхронно (OOM), d уже освобождён внутри */
+        return;
+    }
+#endif
     if (nq->connectivity.probe_status == PROBE_STATUS_IN_PROGRESS) {
         DEBUG_INFO(DEBUG_CATEGORY_BGP, "probe already in progress for node %016llx", (unsigned long long)nq->node_id);
         return;
@@ -386,6 +424,15 @@ void route_connectivity_probe_node(struct UTUN_INSTANCE* instance, struct TOPO_G
 
 void route_connectivity_cancel_node(struct UTUN_INSTANCE* instance, struct TOPO_GROUP_NODE* nq) {
     if (!instance || !nq) return;
+#ifdef UTUN_HAVE_STANDBY
+    {   struct route_probe_defer* d = (struct route_probe_defer*)nq->connectivity.probe_deferred_wait;
+        if (d) {
+            if (d->wait_handle) standby_wait_cancel(d->wait_handle);
+            u_free(d);
+            nq->connectivity.probe_deferred_wait = NULL;
+        }
+    }
+#endif
     nq->connectivity.probe_status = PROBE_STATUS_NONE;
     nq->connectivity.pending_count = 0;
     struct conn_probe_ctx* ctx = (struct conn_probe_ctx*)nq->connectivity.probe_list;
@@ -401,6 +448,15 @@ void route_connectivity_cancel_all(struct UTUN_INSTANCE* instance) {
     struct ll_entry* e = group->nodes->head;
     while (e) {
         struct TOPO_GROUP_NODE* nq = (struct TOPO_GROUP_NODE*)e;
+#ifdef UTUN_HAVE_STANDBY
+        {   struct route_probe_defer* d = (struct route_probe_defer*)nq->connectivity.probe_deferred_wait;
+            if (d) {
+                if (d->wait_handle) standby_wait_cancel(d->wait_handle);
+                u_free(d);
+                nq->connectivity.probe_deferred_wait = NULL;
+            }
+        }
+#endif
         nq->connectivity.probe_status = PROBE_STATUS_NONE;
         nq->connectivity.pending_count = 0;
         e = e->next;
diff --git a/src/routing_layer/topo_group.c b/src/routing_layer/topo_group.c
index aee079dd..43f9cac1 100644
--- a/src/routing_layer/topo_group.c
+++ b/src/routing_layer/topo_group.c
@@ -262,6 +262,7 @@ static void topo_group_destroy(struct TOPO_GROUP* group) {
         struct ll_entry* e; int nc = 0;
         while ((e = queue_data_get(group->nodes)) != NULL) {
             struct TOPO_GROUP_NODE* nq = (struct TOPO_GROUP_NODE*)e;
+            route_connectivity_cancel_node(group->instance, nq);
             if (nq->paths) { queue_free(nq->paths); nq->paths = NULL; }
             topo_nodeq_free_group_fields(group->instance->topo_groups, nq);
             queue_entry_free(e); nc++;
diff --git a/src/routing_layer/topo_group_connect.c b/src/routing_layer/topo_group_connect.c
index 34e4789e..6c56cc71 100644
--- a/src/routing_layer/topo_group_connect.c
+++ b/src/routing_layer/topo_group_connect.c
@@ -12,7 +12,8 @@
  *
  * После исчерпания Phase 3 → пауза → cycle_restart → Phase 1 (бесконечно).
  *
- * Пауза: 1с когда client_activity == ACTIVE, 30с когда STANDBY (Android фон).
+ * Пауза: активный режим — 1с; фоновый (Android standby) — standby_wait
+ * (burst → сразу, sleep → до следующего burst).
  * При DOWN (active_conn_count → 0) — немедленный cycle_restart.
  * При повторном topo_group_connect_init — destroy + fresh init.
  *
@@ -32,6 +33,9 @@
 #include "../lib/ll_queue.h"
 #include "etcp.h"
 #include "../chat/chat_event.h"
+#ifdef UTUN_HAVE_STANDBY
+#include "standby.h"
+#endif
 
 /* ─── внутренние константы ─── */
 #define TGC_ID "topo_group_connect"
@@ -42,13 +46,13 @@
 #define TGC_PHASE_DONE  3
 #define TGC_PHASE_PAUSE 4
 #define TGC_MAX_HANDLES 128
-#define TGC_PAUSE_ACTIVE_TB  10000   /* 1s пауза когда client_activity == ACTIVE */
-#define TGC_PAUSE_IDLE_TB   300000   /* 30s пауза когда STANDBY (Android фон) */
+#define TGC_PAUSE_ACTIVE_TB  10000   /* 1s пауза в активном режиме */
 
 struct TOPO_GROUP_CONNECT {
     struct TOPO_GROUP* group;
     void*  phase_timer;
-    void*  pause_timer;
+    void*  pause_timer;      /* uasync timeout handle (активный режим) */
+    void*  pause_wait;       /* standby_wait handle (фоновый режим, Android) */
     uint8_t phase;
     int    pending;
     int    connected_count;
@@ -149,6 +153,9 @@ void topo_group_connect_destroy(struct TOPO_GROUP* group) {
     group->connect = NULL;
     if (gc->phase_timer) { uasync_cancel_timeout(group->instance->ua, gc->phase_timer); gc->phase_timer = NULL; }
     if (gc->pause_timer) { uasync_cancel_timeout(group->instance->ua, gc->pause_timer); gc->pause_timer = NULL; }
+#ifdef UTUN_HAVE_STANDBY
+    if (gc->pause_wait) { standby_wait_cancel(gc->pause_wait); gc->pause_wait = NULL; }
+#endif
     for (int i = 0; i < gc->handle_count; i++) conn_mgr_close(gc->handles[i]);
     if (gc->cur_handle) { conn_mgr_close(gc->cur_handle); gc->cur_handle = NULL; }
     u_free(gc->candidate_ids);
@@ -327,12 +334,19 @@ static void tgc_callback(struct CONN_MGR_HANDLE* h, uint64_t node_id, uint64_t g
  */
 static void tgc_start_pause(struct TOPO_GROUP_CONNECT* gc, void (*cb)(void*), const char* label) {
     gc->phase = TGC_PHASE_PAUSE;
-    int active = (gc->group->instance->client_activity == CLIENT_ACTIVITY_ACTIVE);
-    int delay_tb = active ? TGC_PAUSE_ACTIVE_TB : TGC_PAUSE_IDLE_TB;
-    gc->pause_timer = uasync_set_timeout(gc->group->instance->ua, delay_tb, gc, cb, label);
     tgc_notify_connecting(gc, NULL, 0);
-    DEBUG_DEBUG(DEBUG_CATEGORY_BGP, "%s: pause %dms (activity=%s) for ch=%s",
-               TGC_ID, delay_tb / 10, active ? "ACTIVE" : "STANDBY", gc->group->channel_id);
+#ifdef UTUN_HAVE_STANDBY
+    if (standby_is_enabled()) {
+        /* фоновый режим: burst → standby_wait будит сразу, sleep → до следующего burst */
+        gc->pause_wait = standby_wait(gc, cb);
+        gc->pause_timer = NULL;
+        DEBUG_DEBUG(DEBUG_CATEGORY_BGP, "%s: pause (standby) for ch=%s", TGC_ID, gc->group->channel_id);
+        return;
+    }
+#endif
+    gc->pause_timer = uasync_set_timeout(gc->group->instance->ua, TGC_PAUSE_ACTIVE_TB, gc, cb, label);
+    DEBUG_DEBUG(DEBUG_CATEGORY_BGP, "%s: pause %dms (active) for ch=%s",
+               TGC_ID, TGC_PAUSE_ACTIVE_TB / 10, gc->group->channel_id);
 }
 
 /* ═══════════════════════════════════════════════════════════════════════
@@ -393,6 +407,7 @@ static void tgc_phase1_timeout(void* arg) {
  * Когда все перебраны — переходит к Phase 3.
  */
 static void tgc_phase2_try_next(struct TOPO_GROUP_CONNECT* gc) {
+    gc->pause_timer = NULL; gc->pause_wait = NULL;
     if (gc->phase == TGC_PHASE_PAUSE) gc->phase = TGC_PHASE_TWO;
     if (gc->phase != TGC_PHASE_TWO) return;
     while (1) {
@@ -439,6 +454,7 @@ static void tgc_phase2_try_next(struct TOPO_GROUP_CONNECT* gc) {
  * пауза и полный перезапуск цикла с Phase 1 (бесконечно, пока не подключимся).
  */
 static void tgc_phase3_try_next(struct TOPO_GROUP_CONNECT* gc) {
+    gc->pause_timer = NULL; gc->pause_wait = NULL;
     if (gc->phase == TGC_PHASE_PAUSE) gc->phase = TGC_PHASE_THREE;
     if (gc->phase != TGC_PHASE_THREE) return;
     if (gc->candidate_count == 0) {
@@ -472,7 +488,7 @@ static void tgc_phase3_try_next(struct TOPO_GROUP_CONNECT* gc) {
  * и после исчерпания Phase 3.
  */
 static void tgc_cycle_restart(struct TOPO_GROUP_CONNECT* gc) {
-    gc->pause_timer = NULL;
+    gc->pause_timer = NULL; gc->pause_wait = NULL;
     if (gc->phase_timer) { uasync_cancel_timeout(gc->group->instance->ua, gc->phase_timer); gc->phase_timer = NULL; }
     for (int i = 0; i < gc->handle_count; i++) conn_mgr_close(gc->handles[i]);
     if (gc->cur_handle) { conn_mgr_close(gc->cur_handle); gc->cur_handle = NULL; }
diff --git a/src/routing_layer/topo_group_connect.h b/src/routing_layer/topo_group_connect.h
index 66c784cc..55d40a5c 100644
--- a/src/routing_layer/topo_group_connect.h
+++ b/src/routing_layer/topo_group_connect.h
@@ -11,7 +11,8 @@
  *             После каждого TIMEOUT — пауза перед следующей попыткой.
  *   После исчерпания Phase 3 → пауза → cycle_restart → Phase 1 (бесконечно).
  *
- * Пауза: 1с когда client_activity == ACTIVE, 30с когда STANDBY (Android фон).
+ * Пауза: активный режим — 1с; фоновый (Android standby) — standby_wait
+ * (burst → сразу, sleep → до следующего burst).
  * При DOWN (active_conn_count → 0) — немедленный cycle_restart из любой фазы.
  * При повторном вызове topo_group_connect_init — destroy + fresh init.
  *
diff --git a/src/routing_layer/topo_node.h b/src/routing_layer/topo_node.h
index da5cffd8..91e4a4f6 100644
--- a/src/routing_layer/topo_node.h
+++ b/src/routing_layer/topo_node.h
@@ -52,6 +52,7 @@ struct UTUN_INSTANCE;
 #define PROBE_STATUS_NONE        0
 #define PROBE_STATUS_IN_PROGRESS 1
 #define PROBE_STATUS_DONE        2
+#define PROBE_STATUS_DEFERRED    3   /* отложена до следующего burst (standby_wait) */
 
 #define PROBE_RESULT_UNKNOWN     0
 #define PROBE_RESULT_REACHABLE   1
@@ -99,6 +100,7 @@ struct TOPO_CONNECTIVITY {
     uint64_t ping_req_time;
     uint64_t last_ping_time;
     void*    probe_list;
+    void*    probe_deferred_wait;   /* контекст отложенной пробы (standby_wait, Android) */
 };
 
 #define PING_TTL_TB (86400ULL * 10000ULL)
diff --git a/src/utun_instance.h b/src/utun_instance.h
index c0df27c1..7446aaca 100644
--- a/src/utun_instance.h
+++ b/src/utun_instance.h
@@ -199,6 +199,7 @@ struct UTUN_INSTANCE {
     uint8_t  client_activity;          // CLIENT_ACTIVITY_STANDBY/ACTIVE
     void*    client_activity_timer;    // uasync timer handle for inactivity timeout
     struct utun_activity_cbk_entry* activity_cbks;  // подписки на смену client_activity
+    uint8_t  standby_enabled;          // 1 = standby duty-cycle активен (chatgui-android)
 
     // TCP proxy server (exit node)
     struct tcp_proxy_server tcp_proxy_server;
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/MainActivity.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/MainActivity.kt
index 513de8e3..0b807aa6 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/MainActivity.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/MainActivity.kt
@@ -7,6 +7,7 @@ import androidx.activity.compose.BackHandler
 import androidx.activity.compose.setContent
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.navigationBarsPadding
 import androidx.compose.material3.SnackbarHost
 import androidx.compose.material3.SnackbarHostState
 import androidx.compose.runtime.*
@@ -133,7 +134,7 @@ class MainActivity : ComponentActivity() {
                         )
                     }
                 }
-                SnackbarHost(snackbarHostState, Modifier.align(Alignment.BottomCenter))
+                SnackbarHost(snackbarHostState, Modifier.align(Alignment.BottomCenter).navigationBarsPadding())
             }
 
             /* Show join dialog after QR scan returns */
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/ConfigProvider.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/ConfigProvider.kt
index 086006f1..d2f5b40c 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/ConfigProvider.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/ConfigProvider.kt
@@ -42,6 +42,9 @@ class ConfigProvider(private val context: Context) {
     private val chatCompressorMaxGainDb = intPreferencesKey("chat_compressor_max_gain_db")
     private val chatCompressorRiseRate = intPreferencesKey("chat_compressor_rise_rate")
     private val chatMediaDownloadMaxPeers = intPreferencesKey("chat_media_download_max_peers")
+    private val chatStandbyActiveSec = intPreferencesKey("chat_standby_active_sec")
+    private val chatStandbySleepSec = intPreferencesKey("chat_standby_sleep_sec")
+    private val chatStandbyMinSleepSec = intPreferencesKey("chat_standby_min_sleep_sec")
     private val firstLaunchDone = booleanPreferencesKey("first_launch_done")
     private val connectionModeKey = stringPreferencesKey("connection_mode")
 
@@ -117,6 +120,9 @@ class ConfigProvider(private val context: Context) {
             key == "chat.compressor_max_gain_db" -> context.dataStore.data.first()[chatCompressorMaxGainDb] ?: 25
             key == "chat.compressor_rise_rate" -> context.dataStore.data.first()[chatCompressorRiseRate] ?: 10
             key == "chat.media_download_max_peers" -> context.dataStore.data.first()[chatMediaDownloadMaxPeers] ?: 3
+            key == "chat.standby_active_sec" -> context.dataStore.data.first()[chatStandbyActiveSec] ?: 2
+            key == "chat.standby_sleep_sec" -> context.dataStore.data.first()[chatStandbySleepSec] ?: 60
+            key == "chat.standby_min_sleep_sec" -> context.dataStore.data.first()[chatStandbyMinSleepSec] ?: 15
             else -> 0
         }
     }
@@ -144,6 +150,9 @@ class ConfigProvider(private val context: Context) {
                 "chat.compressor_max_gain_db" -> prefs[chatCompressorMaxGainDb] = value.toIntOrNull() ?: 25
                 "chat.compressor_rise_rate" -> prefs[chatCompressorRiseRate] = value.toIntOrNull() ?: 10
                 "chat.media_download_max_peers" -> prefs[chatMediaDownloadMaxPeers] = value.toIntOrNull() ?: 3
+                "chat.standby_active_sec" -> prefs[chatStandbyActiveSec] = value.toIntOrNull() ?: 2
+                "chat.standby_sleep_sec" -> prefs[chatStandbySleepSec] = value.toIntOrNull() ?: 60
+                "chat.standby_min_sleep_sec" -> prefs[chatStandbyMinSleepSec] = value.toIntOrNull() ?: 15
             }
         }
     }
@@ -336,6 +345,9 @@ class ConfigProvider(private val context: Context) {
             appendLine("compressor_max_gain_db=$chatCompMaxGain")
             appendLine("compressor_rise_rate=$chatCompRiseRate")
             appendLine("media_download_max_peers=$chatDlMaxPeers")
+            appendLine("standby_active_sec=${getInt("chat.standby_active_sec")}")
+            appendLine("standby_sleep_sec=${getInt("chat.standby_sleep_sec")}")
+            appendLine("standby_min_sleep_sec=${getInt("chat.standby_min_sleep_sec")}")
             appendLine()
             appendLine("[debug]")
             appendLine("console_level=info")
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
index 298700ce..2be57969 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NativeLib.kt
@@ -56,6 +56,9 @@ object NativeLib {
     /* ── App foreground/background (Android lifecycle) ── */
     fun setActive(active: Boolean) { nativeSetActive(active) }
 
+    /* ── External network activity (ConnectivityManager) ── */
+    fun notifyNetworkActive() { nativeNotifyNetworkActive() }
+
     fun sendMessage(channelId: String, text: String) { nativeSendMessage(channelId, text) }
     fun createChannel(name: String, channelId: String) { nativeCreateChannel(name, channelId) }
     fun connectNode(address: String, port: Int, pubkeyHex: String) { nativeConnectNode(address, port, pubkeyHex) }
@@ -144,6 +147,7 @@ object NativeLib {
     private external fun nativeIsResponsive(): Boolean
     private external fun nativeIsRunning(): Boolean
     private external fun nativeSetActive(active: Boolean)
+    private external fun nativeNotifyNetworkActive()
 
     /* ── Channel members JNI ── */
     private external fun nativeGetChannelMembers(channelId: String): String?
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NetworkActivityMonitor.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NetworkActivityMonitor.kt
new file mode 100644
index 00000000..cada37b7
--- /dev/null
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/data/NetworkActivityMonitor.kt
@@ -0,0 +1,48 @@
+package com.utun.chat.data
+
+import android.content.Context
+import android.net.ConnectivityManager
+import android.os.Build
+import com.utun.chat.ChatApplication
+
+/**
+ * Слушатель внешней сетевой активности (ConnectivityManager.OnNetworkActiveListener).
+ *
+ * Пробуждает standby-ядро досрочно: когда в фазе SLEEP прошёл min_sleep,
+ * приход сетевой активности запускает следующий активный цикл раньше.
+ *
+ * В колбэке не делаем тяжёлую работу — только дёшевый JNI-вызов
+ * NativeLib.notifyNetworkActive(), который постит событие на uasync-поток.
+ */
+object NetworkActivityMonitor {
+    private var started = false
+
+    private val listener = ConnectivityManager.OnNetworkActiveListener {
+        NativeLib.notifyNetworkActive()
+    }
+
+    fun start() {
+        if (started) return
+        /* addDefaultNetworkActiveListener доступен с API 28 (P) */
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) return
+        val ctx = ChatApplication.instance.applicationContext
+        val cm = ctx.getSystemService(ConnectivityManager::class.java) ?: return
+        cm.addDefaultNetworkActiveListener(listener)
+        started = true
+        LogManager.addLog("INFO", "NET", "network activity listener started")
+        /* Если сеть уже активна в момент запуска — сразу уведомляем */
+        if (cm.isDefaultNetworkActive) {
+            NativeLib.notifyNetworkActive()
+        }
+    }
+
+    fun stop() {
+        if (!started) return
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.P) return
+        val ctx = ChatApplication.instance.applicationContext
+        val cm = ctx.getSystemService(ConnectivityManager::class.java) ?: return
+        cm.removeDefaultNetworkActiveListener(listener)
+        started = false
+        LogManager.addLog("INFO", "NET", "network activity listener stopped")
+    }
+}
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/headless/HeadlessService.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/headless/HeadlessService.kt
index b58800e4..b4d262c1 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/headless/HeadlessService.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/headless/HeadlessService.kt
@@ -12,6 +12,7 @@ import com.utun.chat.ChatApplication
 import com.utun.chat.MainActivity
 import com.utun.chat.data.LogManager
 import com.utun.chat.data.NativeLib
+import com.utun.chat.data.NetworkActivityMonitor
 
 class HeadlessService : Service() {
     override fun onCreate() {
@@ -45,6 +46,7 @@ class HeadlessService : Service() {
         val ok = NativeLib.start(configText)
         if (ok) {
             LogManager.addLog("INFO", "SRV", "uTun core started")
+            NetworkActivityMonitor.start()
         } else {
             LogManager.addLog("ERROR", "SRV", "uTun start failed")
         }
@@ -52,6 +54,7 @@ class HeadlessService : Service() {
 
     override fun onDestroy() {
         LogManager.addLog("INFO", "SRV", "uTun service stopping")
+        NetworkActivityMonitor.stop()
         NativeLib.stop()
         super.onDestroy()
     }
diff --git a/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/SettingsScreen.kt b/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/SettingsScreen.kt
index ce760e7f..ef58162b 100644
--- a/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/SettingsScreen.kt
+++ b/tools/chatgui-android/app/src/main/java/com/utun/chat/ui/screens/SettingsScreen.kt
@@ -99,6 +99,9 @@ private fun GeneralSettingsTab(vm: ChatViewModel, dirty: Boolean, onDirty: (Bool
     var logFile by remember { mutableStateOf("") }
     var logUdpIp by remember { mutableStateOf("") }
     var logUdpPort by remember { mutableStateOf("") }
+    var standbyActiveSec by remember { mutableStateOf("2") }
+    var standbySleepSec by remember { mutableStateOf("60") }
+    var standbyMinSleepSec by remember { mutableStateOf("15") }
     val pubKey by vm.pubKey.collectAsState()
     val generatingKeys by vm.generatingKeys.collectAsState()
 
@@ -124,6 +127,9 @@ private fun GeneralSettingsTab(vm: ChatViewModel, dirty: Boolean, onDirty: (Bool
         logFile = provider.getString("debug.log_file") ?: "utun.log"
         logUdpIp = provider.getString("log_udp.ip") ?: "192.168.40.250"
         logUdpPort = provider.getInt("log_udp.port").toString().let { if (it == "0") "9999" else it }
+        standbyActiveSec = provider.getInt("chat.standby_active_sec").toString()
+        standbySleepSec = provider.getInt("chat.standby_sleep_sec").toString()
+        standbyMinSleepSec = provider.getInt("chat.standby_min_sleep_sec").toString()
         val port = logUdpPort.toIntOrNull() ?: 0
         if (logUdpIp.isNotEmpty() && port > 0) NativeLib.setUdpLogTarget(logUdpIp, port)
         val stored = provider.getString("debug.categories") ?: ""
@@ -301,6 +307,28 @@ private fun GeneralSettingsTab(vm: ChatViewModel, dirty: Boolean, onDirty: (Bool
 
         HorizontalDivider(Modifier.padding(vertical = 8.dp))
 
+        /* ── Standby (background duty-cycle) ── */
+        Text("Standby", style = MaterialTheme.typography.titleMedium)
+        Row(horizontalArrangement = Arrangement.spacedBy(8.dp)) {
+            OutlinedTextField(standbyActiveSec,
+                { v -> standbyActiveSec = v; val nb = v.toIntOrNull(); if (nb != null && nb in 1..3600) {
+                    scope.launch { provider.setValue("chat.standby_active_sec", v) }; NativeLib.setChatSetting("standby_active_sec", v) } },
+                label = { Text("Active (sec)") }, modifier = Modifier.weight(1f).heightIn(min = 40.dp),
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number), singleLine = true)
+            OutlinedTextField(standbySleepSec,
+                { v -> standbySleepSec = v; val nb = v.toIntOrNull(); if (nb != null && nb in 1..86400) {
+                    scope.launch { provider.setValue("chat.standby_sleep_sec", v) }; NativeLib.setChatSetting("standby_sleep_sec", v) } },
+                label = { Text("Sleep (sec)") }, modifier = Modifier.weight(1f).heightIn(min = 40.dp),
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number), singleLine = true)
+        }
+        OutlinedTextField(standbyMinSleepSec,
+            { v -> standbyMinSleepSec = v; val nb = v.toIntOrNull(); if (nb != null && nb in 1..86400) {
+                scope.launch { provider.setValue("chat.standby_min_sleep_sec", v) }; NativeLib.setChatSetting("standby_min_sleep_sec", v) } },
+            label = { Text("Min sleep (sec)") }, modifier = Modifier.heightIn(min = 40.dp),
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number), singleLine = true)
+
+        HorizontalDivider(Modifier.padding(vertical = 8.dp))
+
         /* Debug */
         Text("Debug", style = MaterialTheme.typography.titleMedium)
         DebugLevelDropdown(label = "Global Level", current = debugLevel.uppercase(), onSelect = setDebug)
diff --git a/tools/chatgui-android/jni_bridge/android_jni_bridge.c b/tools/chatgui-android/jni_bridge/android_jni_bridge.c
index 24e2ce3d..04b7c2a4 100644
--- a/tools/chatgui-android/jni_bridge/android_jni_bridge.c
+++ b/tools/chatgui-android/jni_bridge/android_jni_bridge.c
@@ -13,6 +13,7 @@
 #include "../libutun_lite/instance_lite.h"
 #include "../libutun_lite/voice_recorder.h"
 #include "../libutun_lite/attachment_sender.h"
+#include "../libutun_lite/standby.h"
 #include "../../../lib/debug_config.h"
 #include "../../../lib/u_async.h"
 #include "../../../lib/mem.h"
@@ -384,7 +385,7 @@ char* utun_bridge_encode_invite_link(uint64_t channel_id, const char* password)
         memcpy(data.pubkey, g_cc.inst->my_keys.public_key, INVITE_PUBKEY_SIZE);
     } else {
         sqlite3_stmt* pkst = NULL;
-        snprintf(sql, sizeof(sql), "SELECT public_key FROM nodes WHERE node_id=?");
+        snprintf(sql, sizeof(sql), "SELECT x25519_pubkey FROM nodes WHERE node_id=?");
         if (sqlite3_prepare_v2(db, sql, -1, &pkst, NULL) == SQLITE_OK) {
             sqlite3_bind_int64(pkst, 1, (sqlite3_int64)target_nid);
             if (sqlite3_step(pkst) == SQLITE_ROW) {
@@ -1182,6 +1183,7 @@ static void bridge_set_active_trampoline(void* arg) {
     struct UTUN_INSTANCE* inst = chat_core_get_inst();
     if (!inst) return;
     utun_set_client_activity(inst, active);
+    standby_set_enabled(inst, !active);
     bridge_log(BLEV_DEBUG, "client_activity set to %s", active ? "ACTIVE" : "STANDBY");
 }
 
@@ -1191,6 +1193,18 @@ void utun_bridge_set_active(int active) {
     uasync_post(ua, bridge_set_active_trampoline, (void*)(intptr_t)active);
 }
 
+static void bridge_notify_network_active_trampoline(void* arg) {
+    (void)arg;
+    bridge_log(BLEV_DEBUG, "network activity notified to standby");
+    standby_notify_network_activity();
+}
+
+void utun_bridge_notify_network_active(void) {
+    struct UASYNC* ua = instance_lite_get_uasync();
+    if (!ua) return;
+    uasync_post(ua, bridge_notify_network_active_trampoline, NULL);
+}
+
 void utun_bridge_collect_conn_list(void) {
     instance_lite_collect_conn_list();
 }
@@ -2012,6 +2026,12 @@ JNIEXPORT void JNICALL Java_com_utun_chat_data_NativeLib_nativeSetActive(
     utun_bridge_set_active(active ? 1 : 0);
 }
 
+JNIEXPORT void JNICALL Java_com_utun_chat_data_NativeLib_nativeNotifyNetworkActive(
+    JNIEnv* env, jobject thiz) {
+    (void)env; (void)thiz;
+    utun_bridge_notify_network_active();
+}
+
 /* ── Connection monitor ── */
 
 JNIEXPORT void JNICALL Java_com_utun_chat_data_NativeLib_nativeCollectConnList(
diff --git a/tools/chatgui-android/jni_bridge/android_jni_bridge.h b/tools/chatgui-android/jni_bridge/android_jni_bridge.h
index cbde4f87..a6b63f13 100644
--- a/tools/chatgui-android/jni_bridge/android_jni_bridge.h
+++ b/tools/chatgui-android/jni_bridge/android_jni_bridge.h
@@ -137,6 +137,10 @@ void utun_bridge_on_network_change(void);
 
 void utun_bridge_set_active(int active);
 
+/* ── External network activity (ConnectivityManager) → standby early wake ── */
+
+void utun_bridge_notify_network_active(void);
+
 /* ── Connection monitor (post collect functions to uasync thread) ── */
 
 void utun_bridge_collect_conn_list(void);
diff --git a/tools/chatgui-android/libutun_lite/CMakeLists.txt b/tools/chatgui-android/libutun_lite/CMakeLists.txt
index c0122e9c..f0ce81db 100644
--- a/tools/chatgui-android/libutun_lite/CMakeLists.txt
+++ b/tools/chatgui-android/libutun_lite/CMakeLists.txt
@@ -29,3 +29,5 @@ target_link_libraries(utun_lite PUBLIC
     OpenSSL::Crypto
     ${CMAKE_THREAD_LIBS_INIT}
 )
+
+add_subdirectory(tests)
diff --git a/tools/chatgui-android/libutun_lite/instance_lite.c b/tools/chatgui-android/libutun_lite/instance_lite.c
index ea24e404..e80bffaa 100644
--- a/tools/chatgui-android/libutun_lite/instance_lite.c
+++ b/tools/chatgui-android/libutun_lite/instance_lite.c
@@ -26,6 +26,7 @@
 #include "transport_layer/etcp.h"
 #include "../jni_bridge/android_udp_log.h"
 #include "../jni_bridge/android_jni_bridge.h"
+#include "standby.h"
 #include <pthread.h>
 #include <stdio.h>
 #include <string.h>
@@ -233,6 +234,7 @@ static void* instance_thread(void* arg) {
 
     g_ua = uasync_create();
     if (!g_ua) { IL_LOGE("uasync_create failed"); free_config(config); __atomic_store_n(&g_thread_running, 0, __ATOMIC_RELEASE); pthread_detach(pthread_self()); return NULL; }
+    standby_init(g_ua);
 
     if (config->global.log_udp_ip[0] && config->global.log_udp_port > 0) {
         udp_log_set_target(config->global.log_udp_ip, config->global.log_udp_port);
@@ -245,6 +247,7 @@ static void* instance_thread(void* arg) {
     g_inst = utun_instance_create_from_config(g_ua, config);
     if (!g_inst) {
         IL_LOGE("utun_instance_create_from_config failed");
+        standby_deinit();
         uasync_destroy(g_ua, 0);
         g_ua = NULL;
         u_report_unfreed_blocks();
@@ -279,6 +282,7 @@ static void* instance_thread(void* arg) {
         IL_LOGE("utun_instance_init failed");
         utun_instance_destroy(g_inst);
         g_inst = NULL;
+        standby_deinit();
         uasync_destroy(g_ua, 0);
         g_ua = NULL;
         u_report_unfreed_blocks();
@@ -333,9 +337,11 @@ static void* instance_thread(void* arg) {
         g_inst = NULL;
         uasync_print_resources(g_ua, "AFTER_DESTROY");
         u_report_unfreed_blocks();
+        standby_deinit();
         uasync_destroy(g_ua, 0);
         g_ua = uasync_create();
         if (!g_ua) { IL_LOGE("poll exit: uasync_create failed"); break; }
+        standby_init(g_ua);
 
         chat_event_set_handler(chat_event_forward);
 
@@ -388,6 +394,7 @@ static void* instance_thread(void* arg) {
             g_inst = NULL;
         }
         if (g_ua) {
+            standby_deinit();
             uasync_destroy(g_ua, 0);
             g_ua = NULL;
         }
diff --git a/tools/chatgui-android/libutun_lite/standby.c b/tools/chatgui-android/libutun_lite/standby.c
new file mode 100644
index 00000000..6d26882b
--- /dev/null
+++ b/tools/chatgui-android/libutun_lite/standby.c
@@ -0,0 +1,386 @@
+/*
+ * standby.c — режим standby с duty-cycle (активный/неактивный интервалы)
+ *
+ * Синглтон (одна instance на процесс — как instance_lite.c).
+ * Таймеры только через uasync. Интервалы читаются лениво из chat_setting,
+ * поэтому их изменение через GUI применяется на границе следующей фазы.
+ *
+ * Duty-cycle:
+ *   standby включён → фаза ACTIVE на standby_active_sec, затем SLEEP на
+ *   standby_sleep_sec, и так по кругу, пока standby не выключат.
+ *
+ * Досрочное пробуждение:
+ *   в фазе SLEEP первые standby_min_sleep_sec секунд спим безусловно;
+ *   после них standby_notify_network_activity() (внешняя сетевая активность)
+ *   пробуждает досрочно — следующий цикл как обычно.
+ *
+ * Список ожидающих (standby_wait) — двусвязный список, элементы из memory_pool.
+ * При выходе из standby (или досрочном пробуждении) все wait-таймеры
+ * отменяются, колбэки вызываются сразу.
+ */
+#include "standby.h"
+#include "chat_setting.h"
+#include "utun_instance.h"
+#include "debug_config.h"
+#include "memory_pool.h"
+
+#define STANDBY_TB_PER_SEC 10000   /* timebase = 0.1ms → 1 сек = 10000 TB */
+
+#define PHASE_ACTIVE 0
+#define PHASE_SLEEP  1
+
+struct standby_wait_entry {
+    struct standby_wait_entry* prev;
+    struct standby_wait_entry* next;
+    void* timer_id;                 /* handle uasync_set_timeout */
+    void (*cb)(void* arg);
+    void* arg;
+};
+
+static struct UASYNC* g_ua = NULL;
+static int  g_enabled = 0;
+static int  g_phase = PHASE_ACTIVE;
+static uint64_t g_phase_start_tb = 0;   /* начало текущей фазы */
+static uint64_t g_phase_end_tb = 0;     /* дедлайн текущей фазы */
+static uint64_t g_min_sleep_end_tb = 0; /* до этой точки спим безусловно */
+static void* g_phase_timer = NULL;
+static void (*g_switch_cb)(int enabled, void* arg) = NULL;
+static void* g_switch_arg = NULL;
+
+static struct memory_pool* g_wait_pool = NULL;
+static struct standby_wait_entry* g_wait_head = NULL;
+static struct standby_wait_entry* g_wait_tail = NULL;
+
+/* счётчики для диагностики */
+static uint32_t g_cnt_wakes_timer = 0;
+static uint32_t g_cnt_wakes_early = 0;
+static uint32_t g_cnt_sleeps      = 0;
+static uint32_t g_cnt_net_events  = 0;
+static uint32_t g_cnt_net_ignored = 0;
+
+static int standby_active_sec(void) {
+    return chat_setting_get_int("standby_active_sec", 2);
+}
+
+static int standby_sleep_sec(void) {
+    return chat_setting_get_int("standby_sleep_sec", 60);
+}
+
+static int standby_min_sleep_sec(void) {
+    int m = chat_setting_get_int("standby_min_sleep_sec", 15);
+    if (m < 0) m = 0;
+    int s = standby_sleep_sec();
+    if (m > s) m = s;
+    return m;
+}
+
+/* override интервалов (мс) для тестов: 0 = использовать chat_setting */
+static int g_override = 0;
+static int g_active_ms = 0;
+static int g_sleep_ms = 0;
+static int g_min_sleep_ms = 0;
+
+static int standby_active_tb(void) {
+    return g_override ? g_active_ms * 10 : standby_active_sec() * STANDBY_TB_PER_SEC;
+}
+
+static int standby_sleep_tb(void) {
+    return g_override ? g_sleep_ms * 10 : standby_sleep_sec() * STANDBY_TB_PER_SEC;
+}
+
+static int standby_min_sleep_tb(void) {
+    int m = g_override ? g_min_sleep_ms * 10 : standby_min_sleep_sec() * STANDBY_TB_PER_SEC;
+    if (m < 0) m = 0;
+    int s = standby_sleep_tb();
+    if (m > s) m = s;
+    return m;
+}
+
+/* ── фазовый таймер ── */
+
+static void standby_phase_timer_cb(void* arg);
+
+static void standby_arm_phase(void) {
+    int dur_tb = (g_phase == PHASE_ACTIVE) ? standby_active_tb() : standby_sleep_tb();
+    g_phase_start_tb = get_time_tb();
+    g_phase_end_tb = g_phase_start_tb + (uint64_t)dur_tb;
+    g_min_sleep_end_tb = (g_phase == PHASE_SLEEP)
+        ? g_phase_start_tb + (uint64_t)standby_min_sleep_tb()
+        : 0;
+    g_phase_timer = uasync_set_timeout(g_ua, dur_tb, NULL, standby_phase_timer_cb, "standby_phase");
+    if (!g_phase_timer) {
+        DEBUG_ERROR(DEBUG_CATEGORY_GENERAL, "standby: failed to arm phase timer");
+    }
+}
+
+static void standby_phase_timer_cb(void* arg) {
+    (void)arg;
+    g_phase_timer = NULL;
+    if (!g_enabled) return;
+    uint64_t elapsed = get_time_tb() - g_phase_start_tb;
+    g_phase = (g_phase == PHASE_ACTIVE) ? PHASE_SLEEP : PHASE_ACTIVE;
+    if (g_phase == PHASE_SLEEP) {
+        g_cnt_sleeps++;
+        DEBUG_INFO(DEBUG_CATEGORY_GENERAL,
+                   "standby: SLEEP (active done in %d.%ds, sleep=%dms min_sleep=%dms)",
+                   (int)(elapsed / STANDBY_TB_PER_SEC), (int)((elapsed % STANDBY_TB_PER_SEC) / 1000),
+                   standby_sleep_tb() / 10, standby_min_sleep_tb() / 10);
+    } else {
+        g_cnt_wakes_timer++;
+        DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "standby: WAKE (timer), slept %d.%ds",
+                   (int)(elapsed / STANDBY_TB_PER_SEC), (int)((elapsed % STANDBY_TB_PER_SEC) / 1000));
+    }
+    standby_arm_phase();
+}
+
+/* ── список ожидающих ── */
+
+static struct standby_wait_entry* wait_entry_alloc(void) {
+    if (!g_wait_pool) {
+        g_wait_pool = memory_pool_init(sizeof(struct standby_wait_entry), "standby_pool");
+        if (!g_wait_pool) return NULL;
+    }
+    return (struct standby_wait_entry*)memory_pool_alloc(g_wait_pool);
+}
+
+static void wait_entry_free(struct standby_wait_entry* e) {
+    memory_pool_free(g_wait_pool, e);
+}
+
+static void wait_list_remove(struct standby_wait_entry* e) {
+    if (e->prev) e->prev->next = e->next; else g_wait_head = e->next;
+    if (e->next) e->next->prev = e->prev; else g_wait_tail = e->prev;
+    e->prev = e->next = NULL;
+}
+
+static void wait_list_push(struct standby_wait_entry* e) {
+    e->prev = g_wait_tail;
+    e->next = NULL;
+    if (g_wait_tail) g_wait_tail->next = e; else g_wait_head = e;
+    g_wait_tail = e;
+}
+
+/* Отменяет все wait-таймеры и вызывает их колбэки немедленно.
+ * Сначала отцепляем весь список — новые регистрации в колбэках
+ * (standby_wait) попадут в свежий список и не будут задеты этим проходом. */
+static void standby_wake_all_waiters(void) {
+    struct standby_wait_entry* list = g_wait_head;
+    g_wait_head = g_wait_tail = NULL;
+    while (list) {
+        struct standby_wait_entry* e = list;
+        list = e->next;
+        e->prev = e->next = NULL;
+        if (e->timer_id) {
+            uasync_cancel_timeout(g_ua, e->timer_id);
+            e->timer_id = NULL;
+        }
+        void (*cb)(void*) = e->cb;
+        void* arg = e->arg;
+        wait_entry_free(e);
+        cb(arg);
+    }
+}
+
+static void standby_wait_timer_cb(void* arg) {
+    struct standby_wait_entry* e = (struct standby_wait_entry*)arg;
+    e->timer_id = NULL;
+    wait_list_remove(e);
+    void (*cb)(void*) = e->cb;
+    void* user_arg = e->arg;
+    wait_entry_free(e);
+    cb(user_arg);
+}
+
+/* ── публичный API ── */
+
+void standby_init(struct UASYNC* ua) {
+    g_ua = ua;
+    g_enabled = 0;
+    g_phase = PHASE_ACTIVE;
+    g_phase_timer = NULL;
+    g_cnt_wakes_timer = g_cnt_wakes_early = 0;
+    g_cnt_sleeps = g_cnt_net_events = g_cnt_net_ignored = 0;
+    DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "standby: init (active=%dms sleep=%dms min_sleep=%dms)",
+               standby_active_tb() / 10, standby_sleep_tb() / 10, standby_min_sleep_tb() / 10);
+}
+
+void standby_deinit(void) {
+    if (!g_enabled && !g_phase_timer && !g_wait_head && !g_wait_pool) {
+        g_ua = NULL;
+        return;
+    }
+    if (g_phase_timer && g_ua) {
+        uasync_cancel_timeout(g_ua, g_phase_timer);
+        g_phase_timer = NULL;
+    }
+    while (g_wait_head) {
+        struct standby_wait_entry* e = g_wait_head;
+        if (e->timer_id && g_ua) uasync_cancel_timeout(g_ua, e->timer_id);
+        wait_list_remove(e);
+        wait_entry_free(e);
+    }
+    if (g_wait_pool) {
+        memory_pool_destroy(g_wait_pool);
+        g_wait_pool = NULL;
+    }
+    g_enabled = 0;
+    g_ua = NULL;
+    DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "standby: deinit (wakes_timer=%u wakes_early=%u sleeps=%u net=%u ignored=%u)",
+               g_cnt_wakes_timer, g_cnt_wakes_early, g_cnt_sleeps, g_cnt_net_events, g_cnt_net_ignored);
+}
+
+void standby_set_enabled(struct UTUN_INSTANCE* inst, int enabled) {
+    if (!g_ua) {
+        DEBUG_ERROR(DEBUG_CATEGORY_GENERAL, "standby: set_enabled(%d) but not initialized", enabled);
+        return;
+    }
+    if (g_enabled == enabled) return;
+
+    if (enabled) {
+        g_enabled = 1;
+        g_phase = PHASE_ACTIVE;
+        DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "standby: ENTER (app background, active=%dms sleep=%dms min_sleep=%dms)",
+                   standby_active_tb() / 10, standby_sleep_tb() / 10, standby_min_sleep_tb() / 10);
+        standby_arm_phase();
+    } else {
+        g_enabled = 0;
+        if (g_phase_timer) {
+            uasync_cancel_timeout(g_ua, g_phase_timer);
+            g_phase_timer = NULL;
+        }
+        DEBUG_INFO(DEBUG_CATEGORY_GENERAL, "standby: EXIT (app foreground, wakes_timer=%u wakes_early=%u sleeps=%u net=%u ignored=%u)",
+                   g_cnt_wakes_timer, g_cnt_wakes_early, g_cnt_sleeps, g_cnt_net_events, g_cnt_net_ignored);
+        standby_wake_all_waiters();
+    }
+
+    if (inst) inst->standby_enabled = (uint8_t)enabled;
+    if (g_switch_cb) g_switch_cb(enabled, g_switch_arg);
+}
+
+int standby_is_enabled(void) {
+    return g_enabled;
+}
+
+void standby_set_switch_callback(void (*cb)(int enabled, void* arg), void* arg) {
+    g_switch_cb = cb;
+    g_switch_arg = arg;
+}
+
+int standby_get_sleep_tb(void) {
+    if (!g_enabled) return 0;
+    if (g_phase == PHASE_ACTIVE) return 0;
+    uint64_t now = get_time_tb();
+    if (now >= g_phase_end_tb) return 0;
+    return (int)(g_phase_end_tb - now);
+}
+
+int standby_get_active_remaining_tb(void) {
+    if (!g_enabled) return 0;
+    if (g_phase == PHASE_SLEEP) return 0;
+    uint64_t now = get_time_tb();
+    if (now >= g_phase_end_tb) return 0;
+    return (int)(g_phase_end_tb - now);
+}
+
+void* standby_wait(void* arg, void (*cb)(void* arg)) {
+    if (!cb) return NULL;
+    if (!g_ua) {
+        DEBUG_ERROR(DEBUG_CATEGORY_GENERAL, "standby: wait() but not initialized");
+        return NULL;
+    }
+    if (!g_enabled) {
+        /* standby выключен → будим сразу (отложенно, чтобы не было рекурсии) */
+        uasync_call_soon(g_ua, arg, (timeout_callback_t)cb);
+        return NULL;
+    }
+
+    struct standby_wait_entry* e = wait_entry_alloc();
+    if (!e) {
+        DEBUG_ERROR(DEBUG_CATEGORY_GENERAL, "standby: wait_entry_alloc failed");
+        cb(arg);
+        return NULL;
+    }
+    e->cb = cb;
+    e->arg = arg;
+
+    /* время до начала следующего активного интервала:
+     * SLEEP — ждём до конца фазы; ACTIVE — уже бодрствуем, будим сразу. */
+    uint64_t now = get_time_tb();
+    uint64_t tb;
+    if (g_phase == PHASE_SLEEP) {
+        tb = (now < g_phase_end_tb) ? (g_phase_end_tb - now) : 0;
+    } else {
+        tb = 0;
+    }
+
+    e->timer_id = uasync_set_timeout(g_ua, (int)tb, e, standby_wait_timer_cb, "standby_wait");
+    if (!e->timer_id) {
+        DEBUG_ERROR(DEBUG_CATEGORY_GENERAL, "standby: uasync_set_timeout failed");
+        wait_entry_free(e);
+        cb(arg);
+        return NULL;
+    }
+    wait_list_push(e);
+    return e;
+}
+
+void standby_wait_cancel(void* handle) {
+    if (!handle) return;
+    struct standby_wait_entry* e = (struct standby_wait_entry*)handle;
+    if (e->timer_id && g_ua) {
+        uasync_cancel_timeout(g_ua, e->timer_id);
+        e->timer_id = NULL;
+    }
+    wait_list_remove(e);
+    wait_entry_free(e);
+}
+
+/* ── внешняя сетевая активность ── */
+
+void standby_notify_network_activity(void) {
+    g_cnt_net_events++;
+    if (!g_enabled) {
+        DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "standby: network activity ignored (standby off)");
+        return;
+    }
+    if (g_phase != PHASE_SLEEP) {
+        DEBUG_DEBUG(DEBUG_CATEGORY_GENERAL, "standby: network activity ignored (phase=ACTIVE)");
+        return;
+    }
+
+    uint64_t now = get_time_tb();
+    uint64_t slept = now - g_phase_start_tb;
+    if (now < g_min_sleep_end_tb) {
+        g_cnt_net_ignored++;
+        DEBUG_INFO(DEBUG_CATEGORY_GENERAL,
+                   "standby: network activity caught, min_sleep not elapsed (%d.%ds left)",
+                   (int)((g_min_sleep_end_tb - now) / STANDBY_TB_PER_SEC),
+                   (int)(((g_min_sleep_end_tb - now) % STANDBY_TB_PER_SEC) / 1000));
+        return;
+    }
+
+    g_cnt_wakes_early++;
+    DEBUG_INFO(DEBUG_CATEGORY_GENERAL,
+               "standby: WAKE early (network activity), slept %d.%ds min_sleep=%dms",
+               (int)(slept / STANDBY_TB_PER_SEC), (int)((slept % STANDBY_TB_PER_SEC) / 1000),
+               standby_min_sleep_tb() / 10);
+
+    if (g_phase_timer) {
+        uasync_cancel_timeout(g_ua, g_phase_timer);
+        g_phase_timer = NULL;
+    }
+    g_phase = PHASE_ACTIVE;
+    standby_arm_phase();
+    standby_wake_all_waiters();
+}
+
+void standby_set_intervals_ms(int active_ms, int sleep_ms, int min_sleep_ms) {
+    if (active_ms <= 0 || sleep_ms <= 0) {
+        g_override = 0;
+        return;
+    }
+    g_override = 1;
+    g_active_ms = active_ms;
+    g_sleep_ms = sleep_ms;
+    g_min_sleep_ms = min_sleep_ms < 0 ? 0 : min_sleep_ms;
+}
diff --git a/tools/chatgui-android/libutun_lite/standby.h b/tools/chatgui-android/libutun_lite/standby.h
new file mode 100644
index 00000000..9d6f1c33
--- /dev/null
+++ b/tools/chatgui-android/libutun_lite/standby.h
@@ -0,0 +1,61 @@
+/*
+ * standby.h — режим standby с duty-cycle (активный/неактивный интервалы)
+ *
+ * Для chatgui-android: когда приложение в фоне, вместо постоянной работы
+ * узел периодически просыпается: ACTIVE (X сек) → SLEEP (Y сек) → ACTIVE ...
+ *
+ * Потребители периодической работы используют standby_wait(): колбэк
+ * срабатывает на старте следующего активного интервала, а при выходе из
+ * standby (приложение вернулось в форграунд) — немедленно.
+ */
+#ifndef STANDBY_H
+#define STANDBY_H
+
+#include "u_async.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct UTUN_INSTANCE;
+
+/* Привязать модуль к uasync. Вызывается после каждого uasync_create(). */
+void standby_init(struct UASYNC* ua);
+
+/* Отмена таймеров и освобождение пула (без вызова колбэков). */
+void standby_deinit(void);
+
+/* Включить/выключить standby-режим. Логирует вход/выход (GENERAL info)
+ * и вызывает switch-callback. Флаг дублируется в inst->standby_enabled. */
+void standby_set_enabled(struct UTUN_INSTANCE* inst, int enabled);
+int  standby_is_enabled(void);
+
+/* Колбэк, вызываемый при каждом переключении standby-режима. */
+void standby_set_switch_callback(void (*cb)(int enabled, void* arg), void* arg);
+
+/* Сколько TB спать сейчас (0 = активный интервал или standby выключен). */
+int  standby_get_sleep_tb(void);
+
+/* Сколько TB осталось активного режима (0 = спим или standby выключен). */
+int  standby_get_active_remaining_tb(void);
+
+/* Ждёт до начала следующего активного интервала (как uasync timeout).
+ * При выходе из standby таймер отменяется и cb вызывается немедленно.
+ * Возвращает handle для standby_wait_cancel(). */
+void* standby_wait(void* arg, void (*cb)(void* arg));
+void  standby_wait_cancel(void* handle);
+
+/* Уведомление о внешней сетевой активности (Android ConnectivityManager).
+ * В фазе SLEEP после min_sleep пробуждает досрочно; иначе игнорируется.
+ * Вызывается на uasync-потоке. */
+void  standby_notify_network_activity(void);
+
+/* Переопределить интервалы (мс), минуя chat_setting. Для тестов.
+ * active_ms/sleep_ms <= 0 → вернуться к chat_setting.
+ * min_sleep_ms может быть 0 (реагировать на сетевую активность сразу). */
+void  standby_set_intervals_ms(int active_ms, int sleep_ms, int min_sleep_ms);
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* STANDBY_H */
diff --git a/tools/chatgui-android/libutun_lite/tests/CMakeLists.txt b/tools/chatgui-android/libutun_lite/tests/CMakeLists.txt
new file mode 100644
index 00000000..b6bbf5a8
--- /dev/null
+++ b/tools/chatgui-android/libutun_lite/tests/CMakeLists.txt
@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.16)
+
+add_executable(test_standby
+    test_standby.c
+)
+
+target_link_libraries(test_standby PRIVATE utun_lite pthread)
diff --git a/tools/chatgui-android/libutun_lite/tests/test_standby.c b/tools/chatgui-android/libutun_lite/tests/test_standby.c
new file mode 100644
index 00000000..b9f9d5e1
--- /dev/null
+++ b/tools/chatgui-android/libutun_lite/tests/test_standby.c
@@ -0,0 +1,216 @@
+/*
+ * test_standby.c — юнит-тест модуля standby (chatgui-android)
+ *
+ * Покрывает все сценарии: init, ENTER/EXIT, смену фаз ACTIVE↔SLEEP,
+ * standby_wait во всех фазах, cancel, сетевую активность (игнор/раннее
+ * пробуждение), clamp min_sleep и re-entry в wake_all_waiters.
+ *
+ * Интервалы задаются через standby_set_intervals_ms() (быстрые: 100-300мс).
+ * Время продвигается через uasync_poll(ua, -1) (до ближайшего таймера)
+ * и uasync_poll(ua, X) (частичное ожидание).
+ */
+#include "standby.h"
+#include "debug_config.h"
+#include <stdio.h>
+#include <string.h>
+
+static int g_failures = 0;
+static int g_checks = 0;
+
+#define CHECK(cond, ...) do { \
+    g_checks++; \
+    if (!(cond)) { \
+        g_failures++; \
+        printf("  FAIL: "); printf(__VA_ARGS__); printf("\n"); \
+    } \
+} while (0)
+
+static struct UASYNC* g_ua = NULL;
+
+/* ── колбэки для standby_wait и switch ── */
+
+static int g_wait_calls = 0;
+static void wait_cb(void* arg) {
+    (void)arg;
+    g_wait_calls++;
+}
+
+static int g_switch_calls = 0;
+static int g_switch_last_enabled = -1;
+static void switch_cb(int enabled, void* arg) {
+    (void)arg;
+    g_switch_calls++;
+    g_switch_last_enabled = enabled;
+}
+
+/* re-entry waiter: в колбэке снова регистрирует себя (ровно один раз) */
+static int g_reentry_calls = 0;
+static void reentry_cb(void* arg) {
+    (void)arg;
+    g_reentry_calls++;
+    if (g_reentry_calls == 1) standby_wait(NULL, reentry_cb);
+}
+
+/* ── хелперы ── */
+
+static void reset_standby(void) {
+    standby_deinit();
+    standby_set_intervals_ms(200, 300, 100);  /* active=200ms sleep=300ms min_sleep=100ms */
+    standby_init(g_ua);
+    g_wait_calls = 0;
+    g_switch_calls = 0;
+    g_switch_last_enabled = -1;
+    g_reentry_calls = 0;
+    standby_set_switch_callback(switch_cb, NULL);
+}
+
+/* продвинуть время до ближайшего таймера (фаза переключится) */
+static void run_to_next_phase(void) {
+    uasync_poll(g_ua, -1);
+}
+
+int main(void) {
+    debug_config_init();
+    debug_set_level(DEBUG_LEVEL_INFO);
+
+    g_ua = uasync_create();
+    if (!g_ua) { printf("uasync_create failed\n"); return 1; }
+
+    printf("=== standby unit test ===\n");
+
+    /* ── 1. init ── */
+    reset_standby();
+    CHECK(standby_is_enabled() == 0, "init: should be disabled");
+    CHECK(standby_get_sleep_tb() == 0, "init: sleep_tb should be 0");
+    CHECK(standby_get_active_remaining_tb() == 0, "init: active_remaining should be 0");
+
+    /* ── 2. ENTER ── */
+    standby_set_enabled(NULL, 1);
+    CHECK(standby_is_enabled() == 1, "ENTER: should be enabled");
+    CHECK(standby_get_sleep_tb() == 0, "ENTER: active phase → sleep_tb 0");
+    CHECK(standby_get_active_remaining_tb() > 0, "ENTER: active phase → active_remaining > 0");
+    CHECK(g_switch_calls == 1 && g_switch_last_enabled == 1, "ENTER: switch_cb(1) once");
+
+    /* ── 3. ACTIVE → SLEEP ── */
+    run_to_next_phase();
+    CHECK(standby_get_sleep_tb() > 0, "ACTIVE→SLEEP: sleep_tb > 0");
+    CHECK(standby_get_active_remaining_tb() == 0, "ACTIVE→SLEEP: active_remaining == 0");
+
+    /* ── 4. SLEEP → ACTIVE (по таймеру) ── */
+    run_to_next_phase();
+    CHECK(standby_get_sleep_tb() == 0, "SLEEP→ACTIVE: sleep_tb == 0");
+    CHECK(standby_get_active_remaining_tb() > 0, "SLEEP→ACTIVE: active_remaining > 0");
+
+    /* ── 5. EXIT ── */
+    standby_set_enabled(NULL, 0);
+    CHECK(standby_is_enabled() == 0, "EXIT: should be disabled");
+    CHECK(standby_get_sleep_tb() == 0, "EXIT: sleep_tb == 0");
+    CHECK(g_switch_calls == 2 && g_switch_last_enabled == 0, "EXIT: switch_cb(0)");
+
+    /* ── 6. standby_wait при выключенном → сразу ── */
+    reset_standby();
+    standby_wait(NULL, wait_cb);
+    uasync_poll(g_ua, 0);   /* обработать call_soon */
+    CHECK(g_wait_calls == 1, "wait(disabled): cb fired immediately");
+
+    /* ── 7. standby_wait в ACTIVE → будит сразу (burst, без паузы) ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    standby_wait(NULL, wait_cb);   /* ACTIVE → tb=0, immediate */
+    uasync_poll(g_ua, 0);
+    CHECK(g_wait_calls == 1, "wait(ACTIVE): fired immediately (burst)");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 8. standby_wait в SLEEP → ждёт конца сна ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    CHECK(standby_get_sleep_tb() > 0, "wait(SLEEP): in sleep");
+    standby_wait(NULL, wait_cb);
+    uasync_poll(g_ua, -1);          /* конец сна */
+    uasync_poll(g_ua, 0);
+    CHECK(g_wait_calls == 1, "wait(SLEEP): fired at sleep end");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 9. standby_wait_cancel ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    void* h = standby_wait(NULL, wait_cb);
+    standby_wait_cancel(h);
+    uasync_poll(g_ua, -1);          /* конец сна */
+    uasync_poll(g_ua, 0);
+    CHECK(g_wait_calls == 0, "wait_cancel: cb not called");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 10. notify при standby off → игнор ── */
+    reset_standby();
+    standby_notify_network_activity();
+    CHECK(standby_is_enabled() == 0, "notify(off): still disabled");
+
+    /* ── 11. notify в ACTIVE → игнор ── */
+    standby_set_enabled(NULL, 1);
+    CHECK(standby_get_active_remaining_tb() > 0, "notify(ACTIVE): in active");
+    standby_notify_network_activity();
+    CHECK(standby_get_active_remaining_tb() > 0, "notify(ACTIVE): still active");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 12. notify в SLEEP до min_sleep → игнор ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    CHECK(standby_get_sleep_tb() > 0, "notify(min_sleep): in sleep");
+    standby_notify_network_activity();   /* сразу — ещё < min_sleep(100ms) */
+    CHECK(standby_get_sleep_tb() > 0, "notify(<min_sleep): still sleeping");
+
+    /* ── 13. notify в SLEEP после min_sleep → раннее пробуждение ── */
+    uasync_poll(g_ua, 2000);        /* +200ms → прошло min_sleep(100ms) */
+    standby_notify_network_activity();
+    CHECK(standby_get_sleep_tb() == 0, "notify(>min_sleep): woke → sleep_tb 0");
+    CHECK(standby_get_active_remaining_tb() > 0, "notify(>min_sleep): woke → active_remaining > 0");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 14. раннее пробуждение будит waiters ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    standby_wait(NULL, wait_cb);
+    uasync_poll(g_ua, 2000);        /* +200ms → min_sleep прошёл */
+    standby_notify_network_activity();
+    uasync_poll(g_ua, 0);
+    CHECK(g_wait_calls == 1, "early wake: waiter fired immediately");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 15. clamp min_sleep ≥ sleep → notify всегда игнор ── */
+    reset_standby();
+    standby_set_intervals_ms(200, 300, 500);  /* min_sleep(500) > sleep(300) → clamp */
+    standby_init(g_ua);
+    standby_set_switch_callback(switch_cb, NULL);
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    uasync_poll(g_ua, 2000);        /* +200ms */
+    standby_notify_network_activity();
+    CHECK(standby_get_sleep_tb() > 0, "clamp: min_sleep==sleep → notify ignored");
+    standby_set_enabled(NULL, 0);
+
+    /* ── 16. re-entry: waiter перерегистрируется, без бесконечного цикла ── */
+    reset_standby();
+    standby_set_enabled(NULL, 1);
+    run_to_next_phase();            /* → SLEEP */
+    standby_wait(NULL, reentry_cb);
+    uasync_poll(g_ua, 2000);        /* +200ms → min_sleep прошёл */
+    standby_notify_network_activity();   /* раннее пробуждение → wake_all_waiters */
+    CHECK(g_reentry_calls == 1, "re-entry: wake fired waiter once (no infinite loop)");
+    CHECK(standby_is_enabled() == 1, "re-entry: still enabled after early wake");
+    standby_set_enabled(NULL, 0);   /* EXIT → будит перерегистрированного ещё раз */
+    CHECK(g_reentry_calls == 2, "re-entry: exit fired re-registered waiter once more");
+
+    /* ── итог ── */
+    standby_deinit();
+    uasync_destroy(g_ua, 0);
+
+    printf("=== standby unit test: %d checks, %d failures ===\n", g_checks, g_failures);
+    if (g_failures == 0) printf("PASS\n");
+    else printf("FAIL\n");
+    return g_failures ? 1 : 0;
+}
diff --git a/tools/chatgui-android/libutun_lite/utun_sources.cmake b/tools/chatgui-android/libutun_lite/utun_sources.cmake
index a7fe62c0..0c20a1ac 100644
--- a/tools/chatgui-android/libutun_lite/utun_sources.cmake
+++ b/tools/chatgui-android/libutun_lite/utun_sources.cmake
@@ -37,6 +37,7 @@ function(utun_setup_sources LIB_DIR SRC_DIR CONFIG_DIR TOOLS_DIR)
         "${CONFIG_DIR}/instance_lite.c"
         "${CONFIG_DIR}/voice_recorder.c"
         "${CONFIG_DIR}/attachment_sender.c"
+        "${CONFIG_DIR}/standby.c"
     )
 
     # ── Export sources ──
@@ -67,6 +68,7 @@ function(utun_setup_sources LIB_DIR SRC_DIR CONFIG_DIR TOOLS_DIR)
     # ── Export compile definitions ──
     set(UTUN_DEFINES
         USE_OPENSSL USE_SQLITE _ISOC99_SOURCE _DEFAULT_SOURCE DEBUG_OUTPUT_STDERR
+        UTUN_HAVE_STANDBY
         PARENT_SCOPE
     )
 endfunction()