{
    # /nix/persistent 是你实际保存文件的地方
    environment.persistence."/nix/persistent" = {
        # 不让这些映射的 mount 出现在文件管理器的侧边栏中
        hideMounts = true;

        # 你要映射的文件夹
        directories = [
            "/etc/NetworkManager/system-connections"
            "/root"
            "/var"
            "/boot"
        ];

        files = [
            "/etc/machine-id"
        ];
    };

    environment.variables.NIX_REMOTE = "daemon";

    systemd.services.nix-daemon = {
        environment = {
            # 指定临时文件的位置
            TMPDIR = "/var/cache/nix";
        };
        serviceConfig = {
            # 在 Nix Daemon 启动时自动创建 /var/cache/nix
            CacheDirectory = "nix";
        };
    };

    # Stateless rootfs
    fileSystems."/" = {
        device = "tmpfs";
        fsType = "tmpfs";
        options = [ "relatime" "mode=755" "nosuid" "nodev" ];
    };
}