anchor.diff:  
     raven-go = buildFromGitHub {
       version = 6;
  -    date = "2018-10-18";
  -    rev = "d1aab6ee63f4a2cca2169c538eceba058cb976b7";
  +    rev = "v0.2.0";
       owner  = "getsentry";
       repo   = "raven-go";
  -    sha256 = "e40507240dc5c471432a10e2a22a6742079bb065de0af66eae8e3ad4f8f4e799";
  +    sha256 = "jZK5DYj0EGgU/kELxF+vmi4teI9EuCkary74xkcnrCo=";
       propagatedBuildInputs = [
         errors
         gocertifi
  
positive.code: 
    mafmt = buildFromGitHub {
      version = 6;
      date = "2018-06-27";
      rev = "1dc32401ee9fdd3f6cdb3405ec984d5dae877b2a";
      owner = "whyrusleeping";
      repo = "mafmt";
      sha256 = "13lj4njx1f97zhcanfbfccf8lm8819mzbi260qvibdxni6hsggym";
      propagatedBuildInputs = [
        go-multiaddr
      ];
  
negative.code: 
    go-glob = buildFromGitHub {
      version = 6;
      rev = "v1.0.0";
      owner = "ryanuber";
      repo = "go-glob";
      sha256 = "a89c530d084237d2e615bd3db0ce8f0d44ebdc2c7639bc44853731a6d3140cdf";
    };
  
    go-grpc-middleware = buildFromGitHub {
      version = 6;
      rev = "f849b5445de4819127e123ca96ba0eeb62b5e479";
      owner = "grpc-ecosystem";
      repo = "go-grpc-middleware";
      sha256 = "7c07d8796b8e6c74a5855222bd8e46e579ff08db051207ff18a90ecd4f06d7a5";
      excludedPackages = "\\(testing\\|zap\\)";
      propagatedBuildInputs = [
        grpc
  