diff --git a/piwigo/metadata.yml b/piwigo/metadata.yml
index df8d40f6..ddc5ab83 100644
--- a/piwigo/metadata.yml
+++ b/piwigo/metadata.yml
@@ -25,3 +25,8 @@ uses:
       location: !var-expand "$DATASTORE/$BASE_SERVICE_NAME/opt/apps/piwigo"
       # data-dirs: ## write permission for web-app
       #   - .
+  backup:
+    constraint: optional
+    auto: pair
+    solves:
+      backup: "Automatic regular backup of photos"