anchor.diff:  
     checkInputs = [
       unzip
  -  ];
  -
  -  cmakeFlags = [
  -    "-DCMAKE_SKIP_BUILD_RPATH=OFF" # for tests
     ];
   
     # tests are broken (https://github.com/gdraheim/zziplib/issues/20),
  
positive.code: { stdenv
  , cmake
  , pkg-config
  , ninja
  , fetchFromGitHub
  , fetchpatch
  , zip
  
negative.code:   ];
  
    nativeBuildInputs = [
      perl
      pkg-config
      zip
      python3
      xmlto
  