{
  networking.firewall.allowedTCPPorts =
    [ 80 443 25 465 587 110 995 143 993 29418 ];

  networking.hosts = {
    # Internal IPv4
    "127.0.0.1" = [ "standard" ];
    "127.0.0.2" = [ "clicks" ];
    "127.0.0.3" = [ "caramels" ];
    "127.0.0.255" = [ "generic" ];

    # Internal IPv6
    "[::1]" = [ "standard" ];
    
    # External
    "192.168.0.4" = [ "CodedPi" ];
    "192.168.0.5" = [ "SamuelDesktop" ];
    "192.168.0.6" = [ "d2.a1.clicks" "a1d2.clicks" "a1d2" ];
  };
}