diff --git a/lib/u_async.c b/lib/u_async.c
index 48ba795a..67448299 100644
--- a/lib/u_async.c
+++ b/lib/u_async.c
@@ -450,6 +450,7 @@ static void process_timeouts(struct UASYNC* ua) {
         }
         
         if (node && node->callback) {
+            DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "timer→immediate %s", node->name[0] ? node->name : "");
             node->callback(node->arg);
         }
         
@@ -475,7 +476,7 @@ static void process_timeouts(struct UASYNC* ua) {
         struct timeout_node* node = (struct timeout_node*)entry.data;
         
         if (node && node->callback) {
-            // Execute callback only if not cancelled
+            DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "timer→%s expired", node->name[0] ? node->name : "");
             node->callback(node->arg);
         }
         
@@ -920,6 +921,8 @@ static void process_epoll_events(struct UASYNC* ua, struct epoll_event* events,
         // Socket event — save node fields locally: callbacks may realloc
         // the socket array, invalidating `node`.
         struct socket_node* node = socket_array_get(ua->sockets, events[i].data.fd);
+        DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "poll→fd=%d ev=0x%x%s", events[i].data.fd, events[i].events,
+                    !node || !node->active ? " (inactive)" : "");
         if (!node || !node->active) continue;
         int local_fd = node->fd;
         socket_t local_sock = node->sock;
@@ -972,7 +975,9 @@ void uasync_poll(struct UASYNC* ua, int timeout_tb) {
     if (!ua) return;
     if (!ua->sockets || !ua->timeout_heap) return;
 
-    DEBUG_DEBUG(DEBUG_CATEGORY_TIMERS, "poll");
+    DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "poll(%d sockets, %zu timers, timeout=%d.%dms)",
+                ua->sockets->count, ua->timeout_heap->size, timeout_tb >= 0 ? timeout_tb / 10000 : -1,
+                timeout_tb >= 0 ? (timeout_tb % 10000) / 10 : 0);
     
     // Handle negative or zero timeout
     if (timeout_tb < 0) timeout_tb = -1;  // Infinite wait
@@ -1135,7 +1140,8 @@ void uasync_poll(struct UASYNC* ua, int timeout_tb) {
             int has_write = FD_ISSET(s, &write_fds);
             int has_except = FD_ISSET(s, &except_fds);
             
-            if (!has_read && !has_write && !has_except) continue;
+            if (!has_read && !has_write && !has_except) continue;
+            DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "select→fd=%d r=%d w=%d e=%d", (int)s, has_read, has_write, has_except);
             
             if (has_except) {
                 if (node->except_cbk) {
@@ -1193,7 +1199,8 @@ void uasync_poll(struct UASYNC* ua, int timeout_tb) {
     /* Process socket events first to give sockets higher priority */
     if (ret > 0) {
         for (int i = 0; i < ua->poll_fds_count; i++) {
-            if (ua->poll_fds[i].revents == 0) continue;
+            if (ua->poll_fds[i].revents == 0) continue;
+            DEBUG_DEBUG(DEBUG_CATEGORY_UASYNC, "poll→fd=%d rev=0x%x", ua->poll_fds[i].fd, ua->poll_fds[i].revents);
             
             /* Handle wakeup fd separately */
             if (wakeup_fd_present && i == 0) {