diff --git a/nix/module.nix b/nix/module.nix
index 30a336a..c3a5152 100644
--- a/nix/module.nix
+++ b/nix/module.nix
@@ -14,7 +14,9 @@ in {
 
     timer = lib.mkOption {
       type = types.nullOr types.int;
+
       default = null;
+
       description = lib.mdDoc ''
         The time intervall in seconds the script should be repeated.
       '';