diff --git a/nginx/nginx-dev/prepare.py b/nginx/nginx-dev/prepare.py
index 20b905a..3541a6f 100644
--- a/nginx/nginx-dev/prepare.py
+++ b/nginx/nginx-dev/prepare.py
@@ -31,8 +31,10 @@ for host in hosts:
             add_header Referrer-Policy "no-refferer-when-downgrade" always;
             add_header Content-Security-Policy "default-src * data: 'unsafe-eval' 'unsafe-inline'" always;
 
+            set $pre_domain {pre_domain};
+
             location / {{
-                proxy_pass http://{pre_domain}-nginx:1238$request_uri;
+                proxy_pass http://$pre_domain-nginx:1238$request_uri;
             }}
         }}\n\n
     '''.format(host=host, pre_domain=host.split('.')[0])