anchor.diff:        '';
   
       license = licenses.gpl3Plus;
  -
       maintainers = with maintainers; [ pSub ];
       platforms = platforms.gnu;  # arbitrary choice
     };
  
positive.code: { fetchurl, stdenv, lzip, texinfo }:
  
  stdenv.mkDerivation rec {
    name = "ocrad-0.24";
  
    src = fetchurl {
      url = "mirror://gnu/ocrad/${name}.tar.lz";
      sha256 = "0hhlx072d00bi9qia0nj5izsq4qkscpfz2mpbyfc72msl3hfvslv";
    };
  
    buildInputs = [ lzip texinfo ];
  
negative.code: 
    meta = with stdenv.lib; {
      description = "Optical character recognition (OCR) program & library";
      longDescription =
        '' GNU Ocrad is an OCR (Optical Character Recognition) program based on
           a feature extraction method.  It reads images in pbm (bitmap), pgm
  