diff --git a/docker-compose.yml b/docker-compose.yml
index 35e33d4..9cc492a 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -22,6 +22,9 @@ services:
       MONGO_INITDB_ROOT_USERNAME: ${PYTHON_MONGO_USERNAME:-root}
       MONGO_INITDB_ROOT_PASSWORD: ${PYTHON_MONGO_PASSWORD:?error}
       MONGO_INITDB_DATABASE: ${PYTHON_MONGO_DATABASE:-transparenzregister}
+    ports:
+    - {MONGO_EXTERNAL_PORT:-27018}:27017
+
     volumes:
     - /iscsi/truenas/transparenzregister/mongo_data:/data/db