my-container.nix

{ config, pkgs, ... }:
{
  networking.macvlans.mv-wlan0-host = {
    interface = "wlan0";
    mode = "bridge";
  };
  networking.interfaces.wlan0.ipv4.addresses = pkgs.lib.mkForce [];
  networking.interfaces.mv-wlan0 = {
    ipv4.addresses = [ { address = "192.168.1.1"; prefixLength = 24; } ]; 
  };

  containers.my-container = { 
    autoStart = true;
    macvlans = [ "wlan0" ];
    config = { config, pkgs, ... }:
    {
      networking.interfaces.mv-wlan0 = {
        ipv4.addresses = [ { address = "192.168.1.20"; prefixLength = 24; } ];
      };
    };
  };
}