configuration.nix/hosts/rico0/network.nix

{ lib, ... }: {
  networking = {
    hostName = "Rico0";

    networkmanager = {
      enable = true;
      dhcp = "dhcpcd";
      appendNameservers = [
        "2620:fe::fe"
        "9.9.9.9"
        "2620:fe::9"
        "149.112.112.112"
      ];
    };

    useDHCP = lib.mkDefault false;
  };
}