♻️ config refactor cleanup

nix/shells.nix

@@ -1,16 +1,13 @@
-{ system, self, ... }:
-
-with self.pkgs.${system};
-
+{ system, pkgs, self, ... }:
 let
-  darwin-local = writeScriptBin "darwin-local" ''
-    #!${stdenv.shell}
+  darwin-local = pkgs.writeScriptBin "darwin-local" ''
+    #!${pkgs.stdenv.shell}
     nix build .#darwinConfigurations.$(hostname -s).system
     ./result/sw/bin/darwin-rebuild switch --flake .
   '';
 in
 {
-  default = mkShell {
+  default = pkgs.mkShell {
     name = "athens";
     buildInputs = with pkgs; [
       darwin-local