diff --git a/stack.production.yml b/stack.production.yml
index 1f727d0..01b83a8 100644
--- a/stack.production.yml
+++ b/stack.production.yml
@@ -9,9 +9,9 @@ x-environment: &default-environment
     # PICSUR_PORT: 8080
     PICSUR_DB_HOST: postgres
     PICSUR_DB_PORT: 5432
-    PICSUR_DB_USERNAME: *POSTGRES_USER
-    PICSUR_DB_PASSWORD: *POSTGRES_PASSWORD
-    PICSUR_DB_DATABASE: *POSTGRES_DB
+    PICSUR_DB_USERNAME: ${POSTGRES_USER}
+    PICSUR_DB_PASSWORD: ${POSTGRES_PASSWORD}
+    PICSUR_DB_DATABASE: ${POSTGRES_DB}
     ## The default username is admin, this is not modifyable
     PICSUR_ADMIN_PASSWORD: Jc4SfnnvBD9w3E4w6si8FnreQ8zoUxRco
     ## Optional, random secret will be generated if not set