diff --git a/modules/system/defaults/trackpad.nix b/modules/system/defaults/trackpad.nix
index a86a3477..edb63754 100644
--- a/modules/system/defaults/trackpad.nix
+++ b/modules/system/defaults/trackpad.nix
@@ -13,6 +13,14 @@ with lib;
       '';
     };
 
+    system.defaults.trackpad.Dragging = mkOption {
+      type = types.nullOr types.bool;
+      default = null;
+      description = ''
+        Whether to enable tap-to-drag. The default is false.
+      '';
+    };
+
     system.defaults.trackpad.TrackpadRightClick = mkOption {
       type = types.nullOr types.bool;
       default = null;