anchor.diff:  
       mkdir -p $out/share/applications $out/share/icons/hicolor/32x32/apps
       cp src/HDFView.png $out/share/icons/hicolor/32x32/apps/
  -
  +  '' + lib.optionalString stdenv.isDarwin ''
  +    mkdir -p $out/Applications
  +    cp -a build/dist/HDFView.app $out/Applications/
  +  '' + ''
       runHook postInstall
     '';
   
  
positive.code: 
    installPhase = ''
      runHook preInstall
  
      mkdir -p $out/bin $out/lib
      cp -a build/dist/HDFView/bin/HDFView $out/bin/
      cp -a build/dist/HDFView/lib/app $out/lib/
  
negative.code:     description = "A visual tool for browsing and editing HDF4 and HDF5 files";
      license = lib.licenses.free; # BSD-like
      homepage = "https://portal.hdfgroup.org/display/HDFVIEW/HDFView";
      platforms = lib.platforms.linux ++ lib.platforms.darwin;
    };
  }
  