diff --git a/bundles/nginx/metadata.py b/bundles/nginx/metadata.py
index 99aa6f9..ad25a3c 100644
--- a/bundles/nginx/metadata.py
+++ b/bundles/nginx/metadata.py
@@ -104,7 +104,7 @@ def letsencrypt(metadata):
     return {
         'letsencrypt': {
             'domains': {
-                domain: set() for domain in metadata.get('nginx/vhosts')
+                domain: set() for domain in metadata.get('nginx/vhosts').keys()
             },
             'reload_after': {
                 'nginx',