anchor.diff:  
     go-cache = buildFromGitHub {
       version = 2;
  -    rev = "e7a9def80f35fe1b170b7b8b68871d59dea117e1";
  +    rev = "ea4bd2a538d816ad2bd3426ced3a99f2382103ba";
       owner = "patrickmn";
       repo = "go-cache";
  -    sha256 = "17zkd2lyjfp8rzn3z0d59rbjbkv5w5c7wsb7h33d81rrlj9af7ai";
  -    date = "2016-11-25";
  +    sha256 = "1krybdw5kwv93rzqj12ljhz6kdlzg41lz4m1ml4cwbcslip8s975";
  +    date = "2017-03-26";
     };
     go-checkpoint = buildFromGitHub {
       version = 1;
  
positive.code: 
    tools = buildFromGitHub {
      version = 2;
      rev = "81dff79736a5dfbfa04fdfe7bebdabcd0fd6456a";
      date = "2017-03-21";
      owner = "golang";
      repo = "tools";
      sha256 = "0rrw7ig0s1rpwm6xg8hlngmclyyxv1df54wb3835m7fzxb3kjghk";
      goPackagePath = "golang.org/x/tools";
      goPackageAliases = [ "code.google.com/p/go.tools" ];
  
  
negative.code: 
    go-systemd = buildFromGitHub {
      version = 2;
      rev = "1f9909e51b2dab2487c26d64c8f2e7e580e4c9f5";
      owner = "coreos";
      repo = "go-systemd";
      sha256 = "0xfagwn3hd3j5x4bzsl0i10jxlf3azjh7s3cxacy9bghj1zzp0g9";
      propagatedBuildInputs = [
        dbus
        pkg
        pkgs.systemd_lib
      ];
      date = "2017-03-24";
    };
  
    go-systemd_journal = buildFromGitHub {
  