anchor.diff:    NIX_LDFLAGS = [
       "-rpath ${xorg.libX11}/lib"
     ];
  +
  +  passthru = {
  +    srcVerification = fetchurl {
  +      failEarly = true;
  +      md5Urls = map (n: "${n}.md5") src.urls;
  +      inherit (src) urls outputHash outputHashAlgo;
  +    };
  +  };
   
     meta = with stdenv.lib; {
       description = "The GNU Image Manipulation Program";
  
positive.code:     poppler
      pythonPackages.python
      pythonPackages.pygtk
      xorg.fixesproto
      xorg.libICE
      xorg.libSM
  
negative.code:     libpng
      librsvg
      libtiff
      libwebp
      libwmf
      libzip
      openexr
  