anchor.diff:  
     createFindlibDestdir = true;
   
  -  postPatch = ''
  -    substitute ${./META} META --subst-var-by VERSION "${param.version}"
  +  postPatch = param.postPatchInit + ''
       substituteInPlace Makefile \
         --subst-var-by ZLIB_LIBDIR "${zlib.out}/lib" \
         --subst-var-by ZLIB_INCLUDE "${zlib.dev}/include"
  
positive.code:   param =
      if stdenv.lib.versionAtLeast ocaml.version "4.02"
      then {
        version = "1.07";
        url = "https://github.com/xavierleroy/camlzip/archive/rel107.tar.gz";
        sha256 = "1pdz3zyiczm6c46zfgag2frwq3ljlq044p3a2y4wm2wb4pgz8k9g";
        patches = [];
        installTargets = [ "install-findlib" ];
      } else {
        version = "1.05";
        download_id = "1037";
        url = "http://forge.ocamlcore.org/frs/download.php/${param.download_id}/camlzip-${param.version}.tar.gz";
        sha256 = "930b70c736ab5a7ed1b05220102310a0a2241564786657abe418e834a538d06b";
        patches = [./makefile_1_05.patch];
        installTargets = [ "install" ];
      };
  in
  
  stdenv.mkDerivation {
    name = "camlzip-${param.version}";
  
    src = fetchurl {
      inherit (param) url;
      inherit (param) sha256;
    };
  
    buildInputs = [ocaml findlib];
  
    propagatedBuildInputs = [zlib];
  
  
negative.code:     '';
      license = "LGPL+linking exceptions";
      platforms = ocaml.meta.platforms or [];
      maintainers = with maintainers; [ maggesi ];
    };
  }
  