gistfile1.txt

# See https://github.com/systemd/systemd/issues/9252 and https://github.com/systemd/systemd/pull/12794 and    
  
  systemd = {
    network = {
      enable = true;
      netdevs = {
        "98-bridge" = {
          enable = true;
          netdevConfig = {
            Kind = "bridge";
            Name = "br0";
          };
        };
      };
      networks = {
        "98-bridge" = {
          enable = true;
          matchConfig = { Name = "br0"; };
          networkConfig = {
            Address = "192.168.12.1/24";
            ConfigureWithoutCarrier= "yes";
          };
        };
      };
    };
  };