anchor.diff: -{ stdenv, fetchFromGitHub, fetchurl, makeWrapper
  +{ stdenv, fetchFromGitHub, makeWrapper
   , perl, pandoc, python2Packages, git
   , par2cmdline ? null, par2Support ? true
   }:
  
positive.code:     sha256 = "0wdr399jf64zzzsdvldhrwvnh5xpbghjvslr1j2cwr5y4i36znxf";
    };
  
    buildInputs = [ git python2Packages.python ];
    nativeBuildInputs = [ pandoc perl makeWrapper ];
  
    postPatch = ''
  
negative.code: 
    postInstall = ''
      wrapProgram $out/bin/bup \
        --prefix PATH : ${git}/bin
    '';
  
    meta = {
  