At this point it should be functionally mostly identical to the iptables
  mode, except that it does not (and will not) support Service NodePorts on
  127.0.0.1. (Also note that there are currently no command-line arguments
  for the nftables-specific config; you will need to use a config file if
  you want to set the equivalent of any of the `--iptables-xxx` options.)
  
  As this code is still very new, it has not been heavily optimized yet;