diff --git a/deploy.yml b/deploy.yml
index 0c6791e..7c9ad8c 100644
--- a/deploy.yml
+++ b/deploy.yml
@@ -44,7 +44,7 @@
         restart_policy: unless-stopped
         image: mirror.gcr.io/registry:2
         exposed_ports:
-          - 127.0.0.1:5000:5000
+          - "127.0.0.1:5000:5000"
         volumes:
           - /var/lib/registry:/var/lib/registry
         env: