diff --git a/services/web-ui/nginx.conf b/services/web-ui/nginx.conf
index 25b6bfc..1fcb3de 100644
--- a/services/web-ui/nginx.conf
+++ b/services/web-ui/nginx.conf
@@ -2,6 +2,11 @@ server {
     listen 80;
     server_name _;
 
+    # Docker embedded DNS — defers upstream resolution to request time
+    # This prevents nginx crashing at startup if sibling containers aren't
+    # ready yet (which happens on the first `docker compose up`).
+    resolver 127.0.0.11 valid=10s ipv6=off;
+
     # Allow unlimited client upload size
     client_max_body_size 0;
 
@@ -27,8 +32,9 @@ server {
 
     # API proxy - forward to mam-api service
     location /api/ {
+        set $api_upstream http://mam-api:3000;
         client_max_body_size 0;
-        proxy_pass http://mam-api:3000;
+        proxy_pass $api_upstream;
         proxy_http_version 1.1;
         proxy_set_header Upgrade $http_upgrade;
         proxy_set_header Connection "upgrade";
@@ -45,7 +51,8 @@ server {
 
     # Capture proxy - forward to capture service
     location /capture/ {
-        proxy_pass http://capture:3001;
+        set $capture_upstream http://capture:3001;
+        proxy_pass $capture_upstream;
         proxy_http_version 1.1;
         proxy_set_header Upgrade $http_upgrade;
         proxy_set_header Connection "upgrade";