{ ... }:
{
  config = {
    boot.initrd = {
      availableKernelModules = [ "virtio_net" "virtio_pci" "virtio_mmio" "virtio_blk" "virtio_scsi" "9p" "9pnet_virtio" ];
      kernelModules = [ "virtio_balloon" "virtio_console" "virtio_rng" ];

      postDeviceCommands =
        ''
          # Set the system time from the hardware clock to work around a
          # bug in qemu-kvm > 1.5.2 (where the VM clock is initialised
          # to the *boot time* of the host).
          hwclock -s
        '';
    };

    services.qemuGuest.enable = true;
  };
}