diff --git a/nginx.tmpl b/nginx.tmpl
index ec1a4df..c4ed9b7 100644
--- a/nginx.tmpl
+++ b/nginx.tmpl
@@ -1,5 +1,5 @@
 {{/* Load the json that returns a list of rule names mapped to its respective filepath */}}
-{{ $RULES := parseJson $.Env.RULES }}
+{{ $RULES := parseJson ( or $.Env.RULES "[]" ) }}
 
 {{ $CurrentContainer := where $ "ID" .Docker.CurrentContainerID | first }}