diff --git a/bbmri/modules/directory-sync-compose.yml b/bbmri/modules/directory-sync-compose.yml
index 9776ecb..178f46c 100644
--- a/bbmri/modules/directory-sync-compose.yml
+++ b/bbmri/modules/directory-sync-compose.yml
@@ -1,3 +1,5 @@
+version: "3.7"
+
 services:
   directory_sync_service:
     image: "docker.verbis.dkfz.de/cache/samply/directory_sync_service"