anchor.diff: -{ stdenv, buildOcaml, fetchFromGitHub, ocaml, findlib
  +{ stdenv, fetchFromGitHub, ocaml, findlib, ocamlbuild
   , cstruct, zarith, ounit, result, topkg, ptime
   }:
   
  
positive.code:     inherit (param) sha256;
    };
  
    buildInputs = [ ocaml findlib ounit topkg ];
    propagatedBuildInputs = [ result cstruct zarith ] ++ param.propagatedBuildInputs;
  
    buildPhase = "${topkg.run} build --tests true";
  
negative.code:   } else {
      version = "0.1.3";
      sha256 = "0hpn049i46sdnv2i6m7r6m6ch0jz8argybh71wykbvcqdby08zxj";
      propagatedBuildInputs = [ ];
    };
  in
  
  stdenv.mkDerivation rec {
    name = "ocaml${ocaml.version}-asn1-combinators-${version}";
    inherit (param) version;
  
    src = fetchFromGitHub {
      owner  = "mirleft";
  