anchor.diff:    ghc7 = overrideForGhc7 (extendHaskellPackages nixpkgs.pkgs.haskell.packages.ghc7103);
     ghc7_8 = overrideForGhc7_8 (extendHaskellPackages nixpkgs.pkgs.haskell.packages.ghc784);
     stage2Script = nixpkgs.runCommand "stage2.nix" {
  +    GEN_STAGE2 = builtins.readFile (nixpkgs.path + "/pkgs/development/compilers/ghcjs/gen-stage2.rb");
       buildCommand = ''
  -      ${nixpkgs.path}/pkgs/development/compilers/ghcjs/gen-stage2.rb "${sources.ghcjs-boot}" >"$out"
  +      echo "$GEN_STAGE2" > gen-stage2.rb && chmod +x gen-stage2.rb
  +      patchShebangs .
  +      ./gen-stage2.rb "${sources.ghcjs-boot}" >"$out"
       '';
       buildInputs = with nixpkgs; [
         ruby cabal2nix
  
positive.code:       '';
      };
    };
    ghcjsCompiler = (overrideCabal (ghc.callPackage "${nixpkgs.path}/pkgs/development/compilers/ghcjs" {
      bootPkgs = ghc;
      ghcjsBootSrc = sources.ghcjs-boot;
      shims = sources.shims;
  
negative.code:         doHaddock = false;
        });
  
        ghcWithPackages = selectFrom: self.callPackage (nixpkgs.path + "/pkgs/development/haskell-modules/with-packages-wrapper.nix") {
          inherit (self) llvmPackages;
          haskellPackages = self;
          packages = selectFrom self;
  