diff --git a/hm-module.nix b/hm-module.nix
index c2bdf77..bbf722b 100644
--- a/hm-module.nix
+++ b/hm-module.nix
@@ -26,8 +26,8 @@ in {
           default = false;
         };
         cache_dir = mkOption {
-            type = types.str;
-            default = "source_dir";
+          type = types.str;
+          default = "source_dir";
         };
       };
     };