anchor.diff:    src = fetchFromGitHub {
       owner = "NCAR";
       repo = "wrf-python";
  -    rev = version;
  -    hash = "sha256-+v4FEK0FVE0oAIb18XDTOInHKfxXyykb1ngk9Uxwf0c=";
  +    rev = "refs/tags/v${version}";
  +    hash = "sha256-4iIs/M9fzGJsnKCDSl09OTUoh7j6REBXuutE5uXFe3k=";
     };
   
  +  nativeBuildInputs = [
  +    gfortran
  +  ];
  +
     propagatedBuildInputs = [
  -    wrapt
  +    basemap
       numpy
       setuptools
       xarray
  -  ];
  -
  -  nativeBuildInputs = [
  -    gfortran
  +    wrapt
     ];
   
     checkInputs = [
  
positive.code:   ];
  
    meta = with lib; {
      broken = (stdenv.isLinux && stdenv.isAarch64) || stdenv.isDarwin;
      description = "WRF postprocessing library for Python";
      homepage = "http://wrf-python.rtfd.org";
      license = licenses.asl20;
      maintainers = with maintainers; [ mhaselsteiner ];
    };
  }
  
negative.code:   checkPhase = ''
      runHook preCheck
      cd ./test/ci_tests
      ${python.interpreter} utests.py
      runHook postCheck
    '';
  
  