anchor.diff:  
     google-cloud-go = buildFromGitHub {
       version = 3;
  -    date = "2017-10-02";
  -    rev = "0ceb5a5b67deb9be3a5133e55dcbbf60c57d3c6d";
  +    date = "2017-10-03";
  +    rev = "eaddaf6dd7ee35fd3c2420c8d27478db176b0485";
       owner = "GoogleCloudPlatform";
       repo = "google-cloud-go";
  -    sha256 = "00d9vinn3ryrfhiszf1s66lrh687znddz4nlfpzyplbc9qmmw3q5";
  +    sha256 = "15ybi2j2ii64s19660xb0z21pgjbmj83phrhbg724kg89kwfvn37";
       goPackagePath = "cloud.google.com/go";
       goPackageAliases = [
         "google.golang.org/cloud"
  
positive.code:     ];
      propagatedBuildInputs = [
      ];
      version = 3;
    };
  
    genproto_for_grpc = genproto.override {
  
negative.code: 
    mysql = buildFromGitHub {
      version = 3;
      rev = "a8b7ed4454a6a4f98f85d3ad558cd6d97cec6959";
      owner  = "go-sql-driver";
      repo   = "mysql";
      sha256 = "1hca0wfn9gh40wrgym9zd07gzslw7ijp5ban8z9k4ai7amqdl1ri";
      postPatch = ''
        grep -r '+build appengine' -l | xargs rm
      '';
      date = "2017-10-03";
    };
  
    net-rpc-msgpackrpc = buildFromGitHub {
  