diff --git a/wgkex/worker/mqtt.py b/wgkex/worker/mqtt.py
index 24d9b7e..53a06be 100644
--- a/wgkex/worker/mqtt.py
+++ b/wgkex/worker/mqtt.py
@@ -5,7 +5,7 @@
 import re
 import socket
 import threading
-from typing import Optional, Dict, Any, Union
+from typing import Optional, Any
 
 import paho.mqtt.client as mqtt
 
diff --git a/wgkex/worker/mqtt_test.py b/wgkex/worker/mqtt_test.py
index c960142..bea436f 100644
--- a/wgkex/worker/mqtt_test.py
+++ b/wgkex/worker/mqtt_test.py
@@ -1,8 +1,13 @@
 """Unit tests for mqtt.py"""
+import socket
 import threading
 import unittest
+from time import sleep
+
 import mock
+import paho.mqtt.client
 
+from wgkex.common.mqtt import TOPIC_CONNECTED_PEERS
 from wgkex.worker import mqtt
 
 
@@ -88,6 +93,43 @@ def test_on_message_wireguard_fails_no_domain(self, config_mock, link_mock):
         with self.assertRaises(ValueError):
             mqtt.on_message_wireguard(None, None, mqtt_msg)
 
+    @mock.patch.object(mqtt, "get_config")
+    @mock.patch.object(mqtt, "get_connected_peers_count")
+    def test_publish_metrics_loop_success(self, conn_peers_mock, config_mock):
+        config_mock.return_value = _get_config_mock()
+        conn_peers_mock.return_value = 20
+        mqtt_client = mock.MagicMock(spec=paho.mqtt.client.Client)
+
+        ee = threading.Event()
+        thread = threading.Thread(
+            target=mqtt.publish_metrics_loop,
+            args=(ee, mqtt_client, "_ffmuc_domain.one"),
+        )
+        thread.start()
+
+        i = 0
+        while i < 20 and not mqtt_client.publish.called:
+            i += 1
+            sleep(0.1)
+
+        conn_peers_mock.assert_called_with("wg-domain.one")
+        mqtt_client.publish.assert_called_with(
+            TOPIC_CONNECTED_PEERS.format(
+                domain="_ffmuc_domain.one", worker=socket.gethostname()
+            ),
+            20,
+            retain=True,
+        )
+
+        ee.set()
+
+        i = 0
+        while i < 20 and thread.is_alive():
+            i += 1
+            sleep(0.1)
+
+        self.assertFalse(thread.is_alive())
+
 
 if __name__ == "__main__":
     unittest.main()