diff --git a/duplicati/docker-compose.yml b/duplicati/docker-compose.yml
index 74ac1f4..93400b0 100644
--- a/duplicati/docker-compose.yml
+++ b/duplicati/docker-compose.yml
@@ -6,6 +6,7 @@ services:
       - PUID=0
       - PGID=0
       - TZ=Europe/Warsaw
+      - SETTINGS_ENCRYPTION_KEY=super-secret-backup-key-123
     volumes:
       - ./config:/config
       - /mnt/second_disk/duplicati:/backups