anchor.diff:  
     netlink = buildFromGitHub {
       version = 5;
  -    rev = "3ff4c2196115d804aa1c747781ad2b2a5c73e140";
  +    rev = "ad19ca1a4c3354d3fdc67eac04b1e459038d9474";
       owner  = "vishvananda";
       repo   = "netlink";
  -    sha256 = "1yzh0rwv937p7k2chdaar4pw0wdjahnirn7n959cp8ri0wharrcc";
  -    date = "2017-12-17";
  +    sha256 = "02f10gbx3plrvsinsmad4q3z8any7j7m4v2fj6dwbvr18qvqlz47";
  +    date = "2017-12-24";
       propagatedBuildInputs = [
         netns
         sys
  
positive.code:     version = 5;
      owner = "hashicorp";
      repo = "vault-plugin-auth-gcp";
      rev = "3d64d75591b022ee93e3bb2c28b3293f82f03c82";
      sha256 = "0s27ycba648s3l6i3jxb9wgay4rdiggb6yz57mmjzwb6k0j07v7x";
      date = "2017-12-18";
      propagatedBuildInputs = [
        go-cleanhttp
        google-api-go-client
  
negative.code:       purgeTimestamps = true;
        inherit name;
        url = "https://code.googlesource.com/google-api-go-client/+archive/${rev}.tar.gz";
        sha256 = "09997ahzhdgffcf90sz5rbqyxywmbvx07adzqm2dny25lxlr9d35";
      };
      buildInputs = [
        appengine
  