anchor.diff:        nixpkgs = nixpkgsFunc { system = "x86_64-darwin"; };
       };
     };
  +
   in let this = rec {
     inherit nixpkgs
             nixpkgsCross
  
positive.code:         ruby cabal2nix
        ];
      } "";
      ghcjsCompiler = ghc.callPackage (nixpkgs.path + "/pkgs/development/compilers/ghcjs/base.nix") {
        bootPkgs = ghc;
        ghcjsSrc = sources.ghcjs;
  
negative.code:       shims = sources.shims;
        stage2 = import stage2Script;
      };
  
      ghcjsPackages = nixpkgs.callPackage (nixpkgs.path + "/pkgs/development/haskell-modules") {
        ghc = ghcjsCompiler;
        compilerConfig = nixpkgs.callPackage (nixpkgs.path + "/pkgs/development/haskell-modules/configuration-ghc-8.0.x.nix") { inherit haskellLib; };
        packageSetConfig = nixpkgs.callPackage (nixpkgs.path + "/pkgs/development/haskell-modules/configuration-ghcjs.nix") { inherit haskellLib; };
        inherit haskellLib;
      };
  
  #    TODO: Figure out why this approach doesn't work; it doesn't seem to evaluate our overridden ghc at all
  #    ghcjsPackages = nixpkgs.haskell.packages.ghcjs.override {
  #      ghc = builtins.trace "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX" ghcjsCompiler;
  