anchor.diff: -{ stdenv, fetchurl, libjpeg, pcre, zlib, perl }:
  +{ stdenv, fetchurl, libjpeg, zlib, perl }:
   
   let version = "7.0.0";
   in
  
positive.code: 
    nativeBuildInputs = [ perl ];
  
    buildInputs = [ pcre zlib libjpeg ];
  
    postPatch = ''
      patchShebangs qpdf/fix-qdf
  
negative.code:   meta = with stdenv.lib; {
      homepage = http://qpdf.sourceforge.net/;
      description = "A C++ library and set of programs that inspect and manipulate the structure of PDF files";
      license = licenses.asl20; # as of 7.0.0, people may stay at artistic2
      maintainers = with maintainers; [ abbradar ];
      platforms = platforms.all;
    };
  