anchor.diff:  
     grpc = buildFromGitHub {
       version = 3;
  -    date = "2017-05-19";
  -    rev = "9bf8ea0a8282ebecd1aa474c926e3028f5c22a4c";
  +    date = "2017-05-24";
  +    rev = "72395c537b06215f76e659735c6c827363913869";
       owner = "grpc";
       repo = "grpc-go";
  -    sha256 = "056inq1jv4f5pn3wk2hdff1i3pg0knmlzmspmyx32zs3bkhpzn97";
  +    sha256 = "010mrpvy08pigwmb8dfd86wx41iqj58dm1yc85vx4bj94lnz4zkr";
       goPackagePath = "google.golang.org/grpc";
       goPackageAliases = [
         "github.com/grpc/grpc-go"
  
positive.code: 
    sys = buildFromGitHub {
      version = 3;
      rev = "dbc2be9168a660ef302e04b6ff6406de6f967473";
      date = "2017-05-21";
      owner  = "golang";
      repo   = "sys";
      sha256 = "0hmp3bf1qxfxnirlmsa5bp2nvfrzc6rhwsysc2yxkj1fya87hi0z";
      goPackagePath = "golang.org/x/sys";
    };
  
  
negative.code:     version = 3;
      owner = "moby";
      repo = "moby";
      rev = "e4abe7c2ce9bb496f12adbd6e00713e776fd1807";
      date = "2017-05-24";
      sha256 = "0hgf681cw6i3h7h87af1675357nvl3p1c791lav0mnfgsraz71jc";
      goPackageAliases = [
        "github.com/docker/docker"
      ];
  