anchor.diff:  , useTextJSString ? true
   , iosSdkVersion ? "10.2"
   }:
  -let nixpkgs = nixpkgsFunc ({
  +let all-cabal-hashes = fetchFromGitHub {
  +      owner = "commercialhaskell";
  +      repo = "all-cabal-hashes";
  +      rev = "adb039bba3bb46941c3ee08bdd68f25bf2aa5c60";
  +      sha256 = "0mjkrbifag39gm153v5wn555jq7ckwn8s3f1wwsdw67wmql4gcn7";
  +    };
  +    nixpkgs = nixpkgsFunc ({
         inherit system;
         config = {
           allowUnfree = true;
  
positive.code:         ghc = super.ghc // {
            bootPkgs = super.ghc.bootPkgs.override {
              overrides = self: super: {
                Cabal = self.callPackage "${fetchFromGitHub {
                  owner = "obsidiansystems";
                  repo = "cabal";
                  rev = "34292fadaf90571dba15e84ee66eb601ab8b317f";
                  sha256 = "06rsgrlz0wf88qqjrkj9lyy45h7ijvza04awnbc9ci7igr1syn1c";
                }}/Cabal" {};
              };
            };
          };
  
negative.code:             platform = nixpkgs.pkgs.platforms.armv7l-hf-multiplatform;
            };
            config.allowUnfree = true;
            config.packageOverrides = pkgs: {
              inherit all-cabal-hashes;
            };
          };
          armv7aImpure = armv7a // {
            crossSystem = armv7a.crossSystem // { useAndroidPrebuilt = true; };
  