{ stdenv, fetchFromGitHub, coq }:

let rev_and_sha = {
  "8.6" = {
    rev = "v8.6.0";
    sha256 = "0553pcsy21cyhmns6k9qggzb67az8kl31d0lwlnz08bsqswigzrj";
  };
  "8.7" = {
    rev = "V8.7.0";
    sha256 = "11c4sdmpd3l6jjl4v6k213z9fhrmmm1xnly3zmzam1wrrdif4ghl";
  };
};
in

if ! (rev_and_sha ? "${coq.coq-version}") then
  throw "bignums is not available for Coq ${coq.coq-version}"
else with rev_and_sha."${coq.coq-version}";

stdenv.mkDerivation rec {

  name = "coq${coq.coq-version}-bignums";

  src = fetchFromGitHub {
    owner = "coq";
    repo = "bignums";
    inherit rev sha256;
  };

  buildInputs = [ coq.ocaml coq.camlp5 coq.findlib coq ];

  installFlags = "COQLIB=$(out)/lib/coq/${coq.coq-version}/";

  meta = with stdenv.lib; {
    license = licenses.lgpl2;
    platforms = coq.meta.platforms;
  };

}