This is my example meta-layer containing samples for firewall configuration and initialization. Currently it contains sample config for nftables and startup script of sysvinit.
nftables configuration sample is from nftables wiki: https://wiki.nftables.org/wiki-nftables/index.php/Simple_ruleset_for_a_server
nftables sysvinit script is modified from an old nftables release (I think)