anchor.diff:  
     protobuf = buildFromGitHub {
       version = 2;
  -    rev = "4bd1920723d7b7c925de087aa32e2187708897f7";
  -    date = "2016-11-08";
  +    rev = "8ee79997227bf9b34611aee7946ae64735e6fd93";
  +    date = "2016-11-16";
       owner = "golang";
       repo = "protobuf";
  -    sha256 = "01qdki2gdng9mqabbx7yf4qindrpsyib7l2rq92k7812lndqv24j";
  +    sha256 = "12x7d1m6ryjqj4a1hvg60pgx12acvvc8997zlwfzzzmnb6dbc83q";
       goPackagePath = "github.com/golang/protobuf";
       goPackageAliases = [
         "code.google.com/p/goprotobuf"
  +    ];
  +    buildInputs = [
  +      genproto_protobuf
  +    ];
  +  };
  +
  +  protobuf_genproto = buildFromGitHub {
  +    inherit (protobuf) version rev date owner repo goPackagePath sha256;
  +    subPackages = [
  +      "proto"
  +      "ptypes/any"
       ];
     };
   
  
positive.code: 
    google-cloud-go-compute-metadata = buildFromGitHub {
      inherit (google-cloud-go) rev date owner repo sha256 version goPackagePath goPackageAliases meta;
      subPackages = [ "compute/metadata" "internal" ];
      buildInputs = [ net ];
    };
  
    gopcap = buildFromGitHub {
  
negative.code: 
    google-cloud-go = buildFromGitHub {
      version = 2;
      date = "2016-11-15";
      rev = "30b36efdf5c81a1d3f9fac38e1496c29e8adc420";
      owner = "GoogleCloudPlatform";
      repo = "google-cloud-go";
      sha256 = "e7d33facde617abac9a8cb4500bfbd1492a241e0ac22d36337e0c6891ac37ba6";
      goPackagePath = "cloud.google.com/go";
      goPackageAliases = [
        "google.golang.org/cloud"
  