create service in nixos configuration

sample.nix

  # https://www.reddit.com/r/NixOS/comments/mwbr8t/comment/gvhm2mh/?utm_source=share&utm_medium=web2x&context=3
  systemd.services.touchegg = {
    enable = true;
    description = "Touchégg. The daemon.";
    wantedBy = [ "multi-user.target" ];
    serviceConfig = {
      Type = "simple";
      Group = "input";
      Restart = "on-failure";
      RestartSec = 5;
      ExecStart = "${pkgs.touchegg}/bin/touchegg --daemon";
    };
  };