anchor.diff:      buildPhase = ''
         mkdir .cabal
         touch .cabal/config
  -      rm cabal.project # so that cabal new-freeze does try to use HPDF via git
  +      rm cabal.project # so that cabal new-freeze does not try to use HPDF via git
         HOME=$PWD cabal new-freeze --offline --enable-tests || true
       '';
       installPhase = ''
  
positive.code:   osx-exe        = tttool-exe pkgs-osx
       "0rnn4q0gx670nzb5zp7xpj7kmgqjmxcj2zjl9jqqz8czzlbgzmkh";
    osx-exe-bundle = osx-bundler pkgs-osx osx-exe;
  
    macdylibbundler = pkgs.macdylibbundler;
  
    static-files = sourceByRegex ./. [
      "README.md"
  
negative.code: { checkMaterialization ? false }:
  let
    sources = import nix/sources.nix;
  
    # patch haskell.nix to work around
    # https://github.com/input-output-hk/haskell.nix/issues/917
  