diff --git a/overlay.nix b/overlay.nix
new file mode 100644
index 00000000..e1d6cbf1
--- /dev/null
+++ b/overlay.nix
@@ -0,0 +1,15 @@
+final: _: {
+  nix-darwin = configuration: 
+  let 
+    result = import ./eval-config.nix {
+      inherit (final) lib;
+      modules = [
+        ({ lib, ... }: {
+          config.nixpkgs.pkgs = lib.mkDefault final;
+          config.nixpkgs.source = lib.mkDefault final.path;
+          config.nixpkgs.system = lib.mkDefault final.stdenv.hostPlatform;
+        })
+      ] ++ (if builtins.isList configuration then configuration else [ configuration ]);
+    };
+  in result.config.system.build // result;
+}