{...}: {
  # Set your time zone.
  time.timeZone = "Europe/Prague";
  # Select internationalisation properties.
  i18n.defaultLocale = "en_US.UTF-8";

  i18n.extraLocaleSettings = {
    LC_ADDRESS = "cs_CZ.UTF-8";
    LC_IDENTIFICATION = "cs_CZ.UTF-8";
    LC_MEASUREMENT = "cs_CZ.UTF-8";
    LC_MONETARY = "cs_CZ.UTF-8";
    LC_NAME = "cs_CZ.UTF-8";
    LC_NUMERIC = "cs_CZ.UTF-8";
    LC_PAPER = "cs_CZ.UTF-8";
    LC_TELEPHONE = "cs_CZ.UTF-8";
    LC_TIME = "cs_CZ.UTF-8";
  };

  services.xserver = {
    xkb.layout = "us,cz";
    xkb.options = "grp:win_space_toggle";
  };
}