diff --git a/vdf/docker-compose.yml b/vdf/docker-compose.yml
index c3fdbeb..f7796f0 100644
--- a/vdf/docker-compose.yml
+++ b/vdf/docker-compose.yml
@@ -10,4 +10,4 @@ services:
     deploy:
       placement:
         constraints:
-          - node.hostname = gamma
+          - node.hostname == gamma