{
    sound.enable = true;
    networking.networkmanager.enable = true;
    time.timeZone = "Asia/Shanghai";
    security.sudo.wheelNeedsPassword = false;

    hardware = {
        opengl.enable = true;
    };

    # Select internationalisation properties.
    i18n = {
        defaultLocale = "zh_CN.UTF-8";
        extraLocaleSettings = {
            LC_ADDRESS = "zh_CN.UTF-8";
            LC_IDENTIFICATION = "zh_CN.UTF-8";
            LC_MEASUREMENT = "zh_CN.UTF-8";
            LC_MONETARY = "zh_CN.UTF-8";
            LC_NAME = "zh_CN.UTF-8";
            LC_NUMERIC = "zh_CN.UTF-8";
            LC_PAPER = "zh_CN.UTF-8";
            LC_TELEPHONE = "zh_CN.UTF-8";
            LC_TIME = "zh_CN.UTF-8";
        };
    };

    nix.settings = {
        auto-optimise-store = true;
        experimental-features = [
            "nix-command"
            "flakes"
        ];
    };
    nix.gc.automatic = true;

}