diff --git a/source/conf.ts b/source/conf.ts
index e42d4dd..dda1136 100644
--- a/source/conf.ts
+++ b/source/conf.ts
@@ -207,8 +207,13 @@ namespace _zeitbild.conf
 					"lifetime": {
 						"nullable": false,
 						"type": "integer",
-						"default": 900
-					}
+						"default": 3600,
+					},
+					"prolongation": {
+						"nullable": true,
+						"type": "integer",
+						"default": 300,
+					},
 				},
 				"required": [
 				],