anchor.diff:  { stdenv
   , fetchurl
  +, lib
   , perl
   }:
   
   let
  -  version = "1.9.2";
  +  version = "1.9.3";
   in
   stdenv.mkDerivation rec {
     name = "libbson-${version}";
  
positive.code:   src = fetchurl {
      url = "https://github.com/mongodb/libbson/releases/download"
        + "/${version}/${name}.tar.gz";
      sha256 = "0d1de4aa2ea4b223414c1b1aa803fc50d1ab658b327aead857fb4915136d4e34";
    };
  
    nativeBuildInputs = [
  
negative.code:     ln -sv . "$incdir"
    '';
  
    meta = with lib; {
      maintainers = with maintainers; [
        wkennington
      ];
  