anchor.diff:      zfs_arc = {};
       zone = {};
       zookeeper = {};
  +    xencpu = {
  +      buildInputs = [ xen ];
  +    };
     };
   
     configureFlags =
  
positive.code: , rrdtool
  , udev
  , varnish
  , yajl
  # Defaults to `null` for all supported plugins,
  # list of plugin names for a custom build
  
negative.code:     intel_rdt = {};
      interface = {};
      ipc = {};
      ipmi = {
        buildInputs = [ openipmi ];
      };
      iptables = {
        buildInputs = [
          libpcap
  