anchor.diff:    };
   
     internal = buildFromGitHub {
  -    version = 1;
  -    rev = "fbe290d56cdd8bb25347df893b14e3454f07bf7a";
  +    version = 3;
  +    rev = "4747030f7cf2f4c0a01512b00cd68734b167ac3b";
       owner  = "cznic";
       repo   = "internal";
  -    sha256 = "0x80s83nq75xajyqspzcgj2mq5gxw9psxghvb676q8y96jn1n10k";
  -    date = "2016-07-19";
  +    sha256 = "0kmsbgr8qjqxbzymnb0hyk7xickqddzlmffpl7rjw88jmpafks0a";
  +    date = "2017-09-05";
       buildInputs = [
         fileutil
         mathutil
  
positive.code:   };
  
    zappy = buildFromGitHub {
      version = 1;
      date = "2016-07-23";
      rev = "2533cb5b45cc6c07421468ce262899ddc9d53fba";
      owner = "cznic";
      repo = "zappy";
      sha256 = "1fn4kqiggz6b5srkqhn37nwsi381x6hx3n83cbg0fxcb7zb3b6xl";
      buildInputs = [
        mathutil
      ];
      extraSrcs = [
        {
          inherit (internal)
            goPackagePath
            src;
        }
      ];
    };
  }; in self
  
negative.code:       sortutil
      ];
      extraSrcs = [
        internal
        zappy
      ];
      meta.useUnstable = true;
      date = "2016-11-02";
  