anchor.diff:  
   let
     mupdf_src = fetchurl {
  -    url = http://www.mupdf.com/downloads/archive/mupdf-1.5-source.tar.gz;
  -    sha256 = "0sl47zqf4c9fhs4h5zg046vixjmwgy4vhljhr5g4md733nash7z4";
  +    url = http://www.mupdf.com/downloads/archive/mupdf-1.6-source.tar.gz;
  +    sha256 = "0qx51rj6alzcagcixm59rvdpm54w6syrwr4184v439jh14ryw4wq";
     };
   
     tess_src = fetchurl {
  
positive.code:     make libs
      cp src/libPgm2asc.a $plibs/lib
  
      cd ../mupdf-1.5-source
      make prefix=$plibs install
      install -Dm644 build/debug/libmujs.a $plibs/lib
  
  
negative.code: 
  in stdenv.mkDerivation rec {
    name = "k2pdfopt-${version}";
    version = "2.32";
    src = fetchzip {
      url = "http://www.willus.com/k2pdfopt/src/k2pdfopt_v${version}_src.zip";
      sha256 = "1v3cj5bwpjvy7s66sfqcmkxs91f7nxaykjpdjm2wn87vn6q7n19m";
    };
  
    buildInputs = [ libX11 libXext autoconf automake libtool leptonica libpng libtiff zlib
  