nixos/config/networking.nix

{
  config,
  lib,
  ...
}:
with lib; let
  inherit (config.machine) networkD;
in {
  networking = {
    inherit (config.machine) hostName;
    useNetworkd = networkD.enable;
    useDHCP = !networkD.enable;
    dhcpcd.enable = !networkD.enable;
  };
  # Based on
  # https://github.com/NixOS/nixpkgs/issues/10001#issuecomment-905532069
  systemd.network = mkIf networkD.enable {
    enable = true;
    networks = let
      networkConfig = {
        DHCP = "yes";
        DNSSEC = "yes";
        DNSOverTLS = "yes";
        DNS = ["1.1.1.1" "1.0.0.1"];
      };
    in {
      "40-wired" = {
        enable = true;
        name = "en*";
        dhcpV4Config.RouteMetric = 2048;
        inherit networkConfig;
      };
      "40-wireless" = {
        enable = true;
        name = "wl*";
        dhcpV4Config.RouteMetric = 1024;
        inherit networkConfig;
      };
      "50-vlan" = {
        enable = true;
        matchConfig = {
          Name = "br0";
        };
        networkConfig = {
          DNS = "10.0.0.1";
          Address = "10.0.0.100/16";
          # DHCPServer = true;
          # IPMasquerade = true;
        };
        # dhcpServerConfig = {
        # ServerAddress = "172.16.9.1/12";
        # PoolOffset = 100;
        # EmitDNS = false;
        # };
      };
    };
  };
  # Wait for any interface to become available, not for all
  systemd.services."systemd-networkd-wait-online" = {
    enable = mkForce networkD.waitOnline;
    serviceConfig.ExecStart = [
      ""
      "${config.systemd.package}/lib/systemd/systemd-networkd-wait-online --any"
    ];
  };
}