anchor.diff:  
     google-cloud-go = buildFromGitHub {
       version = 2;
  -    date = "2017-02-15";
  -    rev = "a36575d2d41a1a6fbd1de1bb4509ef4c7dbef985";
  +    date = "2017-02-16";
  +    rev = "0b87d14d90086b53a97dfbd66f3000f7f112b494";
       owner = "GoogleCloudPlatform";
       repo = "google-cloud-go";
  -    sha256 = "1ng49a9glka4j70dlfsb1cqv6mz83kv2s24syfms3awyk7k33hyy";
  +    sha256 = "145fsk3v68faaf514v3yqz3lwgip1a3whwy637pds0i1w16dwdvk";
       goPackagePath = "cloud.google.com/go";
       goPackageAliases = [
         "google.golang.org/cloud"
  
positive.code:       testify
      ];
      meta.useUnstable = true;
      date = "2017-02-09";
    };
  
    cupcake_rdb = buildFromGitHub {
  
negative.code: 
    grpc = buildFromGitHub {
      version = 2;
      date = "2017-02-15";
      rev = "d0c32ee6a441117d49856d6120ca9552af413ee0";
      owner = "grpc";
      repo = "grpc-go";
      sha256 = "0idijjxm1y8pj9gx85gp2z4xwrcw3apsdlkjk49w8pws4wak9xn9";
      goPackagePath = "google.golang.org/grpc";
      goPackageAliases = [
        "github.com/grpc/grpc-go"
  