diff --git a/docker/nginx/nginx.conf b/docker/nginx/nginx.conf
index fdb5e0a50..da570f709 100644
--- a/docker/nginx/nginx.conf
+++ b/docker/nginx/nginx.conf
@@ -18,21 +18,20 @@ http {
     resolver 127.0.0.11 valid=10s ipv6=off;
 
     # Upstream servers (using Docker service names)
-    # NOTE: add `resolve` so nginx re-resolves container IPs after restarts.
-    # Otherwise nginx may keep stale DNS results and proxy to the wrong container.
+    # NOTE: `zone` and `resolve` are nginx Plus-only features and are not
+    # available in the standard nginx:alpine image. Docker's internal DNS
+    # (127.0.0.11) handles service discovery; upstreams are resolved at
+    # nginx startup and remain valid for the lifetime of the deployment.
     upstream gateway {
-        zone gateway 64k;
-        server gateway:8001 resolve;
+        server gateway:8001;
     }
 
     upstream langgraph {
-        zone langgraph 64k;
-        server langgraph:2024 resolve;
+        server langgraph:2024;
     }
 
     upstream frontend {
-        zone frontend 64k;
-        server frontend:3000 resolve;
+        server frontend:3000;
     }
 
     # ── Main server (path-based routing) ─────────────────────────────────