anchor.diff:        sha256 = "10wma4hh9l8hk49rl8nql6ixsvlz3163gcxspay5fwrpbg51fmxr";
       };
       "opam-file-format" = fetchurl {
  -      url = "https://github.com/ocaml/opam-file-format/archive/2.1.3.tar.gz";
  -      sha256 = "1bqyrlsvmjf4gqzmzbiyja9m1ph30ic9i18x23p5ziymyylw2sfg";
  +      url = "https://github.com/ocaml/opam-file-format/archive/2.1.4.tar.gz";
  +      sha256 = "0xbdlpxb0348pbwijna2x6nbi8fcxdh63cwrznn4q4zzbv9zsy02";
       };
       "re" = fetchurl {
  -      url = "https://github.com/ocaml/ocaml-re/releases/download/1.9.0/re-1.9.0.tbz";
  -      sha256 = "1gas4ky49zgxph3870nffzkr6y41kkpqp4nj38pz1gh49zcf12aj";
  +      url = "https://github.com/ocaml/ocaml-re/releases/download/1.10.3/re-1.10.3.tbz";
  +      sha256 = "1fqfg609996bgxr14yyfxhvl6hm9c1j0mm2xjdjigqrzgyb4crc4";
       };
       "result" = fetchurl {
         url = "https://github.com/janestreet/result/releases/download/1.5/result-1.5.tbz";
  
positive.code:       sha256 = "1mh6fv8qbf8xx4h2dc0dpv2lzygvikzjhw1idrknibbwsjw3jg9c";
      };
      "dune-local" = fetchurl {
        url = "https://github.com/ocaml/dune/releases/download/2.9.0/dune-2.9.0.tbz";
        sha256 = "07m476kgagpd6kzm3jq30yfxqspr2hychah0xfqs14z82zxpq8dv";
      };
      "extlib" = fetchurl {
        url = "https://ygrek.org/p/release/ocaml-extlib/extlib-1.7.7.tar.gz";
  
negative.code:       sha256 = "0jnqsv6pqp5b5g7lcjwgd75zqqvcwcl5a32zi03zg1kvj79p5gxs";
      };
      opam = fetchurl {
        url = "https://github.com/ocaml/opam/archive/2.1.3.zip";
        sha256 = "08n72n5wc476p28ypxjs8fmlvcb42129fcva753gqm0xicqh24xf";
      };
    };
  in stdenv.mkDerivation {
    pname = "opam";
    version = "2.1.3";
  
    nativeBuildInputs = [ makeWrapper unzip ];
    buildInputs = [ curl ncurses ocaml getconf ] ++ lib.optional stdenv.isLinux bubblewrap;
  