anchor.diff:  
   let
     pname = "vector";
  -  version = "0.21.0";
  +  version = "0.21.1";
   in
   rustPlatform.buildRustPackage {
     inherit pname version;
  
positive.code:     owner = "timberio";
      repo = pname;
      rev = "v${version}";
      sha256 = "sha256-ZhOtrv63ZhG3OEWLTk+VdZr6Y6f9KvyCJvAKWck7B7o=";
    };
  
    cargoSha256 = "sha256-VGB+ljojXGrQmcN0AT90hFk9h5nwjDTtzGpWmItw9x4=";
    nativeBuildInputs = [ pkg-config cmake perl ];
    buildInputs = [ oniguruma openssl protobuf rdkafka zstd ]
      ++ lib.optionals stdenv.isDarwin [ Security libiconv coreutils CoreServices ];
  
negative.code:   buildFeatures = features;
  
    # TODO investigate compilation failure for tests
    # there are about 100 tests failing (out of 1100) for version 0.21.1
    doCheck = false;
  
    checkFlags = [
      # tries to make a network access
  