diff --git a/nginx.conf.template b/nginx.conf.template
index 65ac465..cd5e196 100644
--- a/nginx.conf.template
+++ b/nginx.conf.template
@@ -34,5 +34,13 @@ server {
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
         proxy_set_header X-Forwarded-Proto $scheme;
         proxy_set_header X-Forwarded-Host $host;
+
+        # Disable caching through the double-proxy chain (NPM → frontend nginx → API)
+        # Without this, browsers cache responses keyed by the HTTPS origin, then send
+        # conditional requests (If-None-Match) that get lost or mismatched in the proxy chain.
+        proxy_cache off;
+        add_header Cache-Control "no-store, no-cache, must-revalidate" always;
+        add_header Pragma "no-cache" always;
+        add_header Vary "*" always;
     }
 }