anchor.diff:        find . -name \*_classic.go -delete
         rm internal/main.go
       '';
  -    date = "2017-07-07";
  +    date = "2017-08-01";
     };
   
     arch = buildFromGitHub {
  
positive.code: 
    protobuf = buildFromGitHub {
      version = 3;
      rev = "0a4f71a498b7c4812f64969510bcb4eca251e33a";
      date = "2017-07-12";
      owner = "golang";
      repo = "protobuf";
      sha256 = "1a3csg3m7s3yi6kwd2n6qfyml4pifgnm7y5vylgva8mh7gp9j7hj";
      goPackagePath = "github.com/golang/protobuf";
      buildInputs = [
        genproto_protobuf
  
negative.code: 
    crypto = buildFromGitHub {
      version = 3;
      rev = "558b6879de74bc843225cde5686419267ff707ca";
      date = "2017-07-28";
      owner = "golang";
      repo = "crypto";
      sha256 = "00ws0fhnbn38s2qsfb57xdh5zgwmnlw0wrd08xqy6ivbrllpznq3";
      goPackagePath = "golang.org/x/crypto";
      buildInputs = [
        net_crypto_lib
      ];
      propagatedBuildInputs = [
        sys
      ];
    };
  