anchor.diff:  in let this = rec {
     overrideForGhcjs = haskellPackages: haskellPackages.override {
       overrides = self: super: {
  -    /*
  -      mkDerivation = drv: super.mkDerivation.override {
  -        hscolour = ghc.hscolour;
  -      } (drv // {
  -        doHaddock = false;
  -      });
  -    */
  -
         ghcWithPackages = selectFrom: self.callPackage (nixpkgs.path + "/pkgs/development/haskell-modules/with-packages-wrapper.nix") {
           inherit (self) llvmPackages;
           haskellPackages = self;
  
positive.code:     addExposeAllUnfoldingsFlag = if enableExposeAllUnfoldings
        then drv: appendConfigureFlag drv "-fexpose-all-unfoldings"
        else drv: drv;
      extendHaskellPackages = haskellPackages: makeRecursivelyOverridable haskellPackages {
        overrides = self: super:
          let reflexDom = import ./reflex-dom self nixpkgs;
  
negative.code:           doCheck = false;
          });
  
          ########################################################################
          # Fixes to be upstreamed
          ########################################################################
          foundation = if system == "i686-linux" then dontCheck super.foundation else super.foundation; # TODO: We should make sure these test failures get fixed
          MonadCatchIO-transformers = doJailbreak super.MonadCatchIO-transformers;
          blaze-builder-enumerator = doJailbreak super.blaze-builder-enumerator;
  
        } // (if enableLibraryProfiling && !(super.ghc.isGhcjs or false) then {
          mkDerivation = expr: super.mkDerivation (expr // { enableLibraryProfiling = true; });
  