anchor.diff:      version = 5;
       owner = "elves";
       repo = "elvish";
  -    rev = "3d4bb53dfc300d57c2c5a16c76191765ffc6b889";
  -    sha256 = "0fnmn8cavv4qr6d1fi5gpnisrh1990r206mwgyjy4gnk59w2092y";
  +    rev = "2f834da5c0f275607c576841182ed71878a6d971";
  +    sha256 = "0gf55a6xfmgx5l71scs8l8wpnq6x2x0sha90wgj8ji50sl9d7y79";
       propagatedBuildInputs = [
         bolt
         go-isatty
  
positive.code: 
    sys = buildFromGitHub {
      version = 5;
      rev = "7dca6fe1f43775aa6d1334576870ff63f978f539";
      date = "2018-03-08";
      owner  = "golang";
      repo   = "sys";
      sha256 = "10rpr4lasgriazbx9i5693f821s94dh2hg4r0h81i7984bh1k3i3";
      goPackagePath = "golang.org/x/sys";
    };
  
  
negative.code:       sys
      ];
      meta.useUnstable = true;
      date = "2018-03-16";
    };
  
    eme = buildFromGitHub {
  