anchor.diff:    environment.darwinConfig = "$HOME/.config/nixpkgs/darwin/configuration.nix";
   
     nix.nixPath =
  -    [ # Use local nixpkgs checkout instead of channels.
  -      "darwin-config=$HOME/.config/nixpkgs/darwin/configuration.nix"
  -      "darwin=$HOME/.nix-defexpr/darwin"
  -      "nixpkgs=$HOME/.nix-defexpr/nixpkgs"
  +    [{ # Use local nixpkgs checkout instead of channels.
  +      darwin-config = "$HOME/.config/nixpkgs/darwin/configuration.nix";
  +      darwin = "$HOME/.nix-defexpr/darwin"; }
       ];
   
     nixpkgs.config.allowUnfree = true;
  
positive.code:             hdiutil detach "$dev"
          fi
          diskutil erasevolume JHFS+ RAM $(hdiutil attach -nomount ram://10248576)
      }
  
      install_name_tool() {
  
negative.code:         echo "https://github.com/NixOS/nixpkgs/archive/''${@:-master}.tar.gz"
      }
  
      pr-nixpkgs() {
          local pr=$1
          shift 1
  