Problem on LXQt service definition

["Reza Alizadeh Majd" <r.majd@pantherx.org>]

Hi, 

I'll try to create a service for `lxqt-desktop` based on same definition on [nixos](https://github.com/NixOS/nixpkgs/blob/master/nixos/modules/services/x11/desktop-managers/lxqt.nix). 
but my service definition won't start and  here is my proposed definition for this service:


;;;
;;; LXQt desktop service.
;;;

(define-record-type* <lxqt-desktop-configuration> lxqt-desktop-configuration
  make-lxqt-desktop-configuration
  lxqt-desktop-configuration
  (lxqt-package lxqt-package (default lxqt)))

(define (lxqt-shepherd-service config)
  "Return a shepherd service for @command{lxqt-session}"
  (let ((lxqt-session ((package-direct-input-selector "lxqt-session") 
                       (lxqt-package config))))
    (list (shepherd-service
            (provision '(lxqt))
            ; (requirement '())
            (documentation "Run the lxqt session")
            (start #~(make-forkexec-constructor
                      (list(string-append #$lxqt-session "/bin/startlxqt"))
                      #:environment-variables
                      (list (string-append "XDG_CONFIG_DIRS=" 
                                           "$XDG_CONFIG_DIRS;/run/current-system/profile/etc/xdg")
                            (string-append "XDG_DATA_DIRS="
                                           "$XDG_DATA_DIRS;/run/current-system/profile/share"))
            (stop #~(make-kill-destructor))))))

(define lxqt-desktop-service-type
  (service-type
    (name 'lxqt-desktop)
    (extensions
      (list
            (service-extension shepherd-root-service-type
                               lxqt-shepherd-service)
            (service-extension profile-service-type
                               (compose list 
                                        lxqt-package))))
    (default-value (lxqt-desktop-configuration))
    (description "Run the LXQt desktop environment.")))

(define-deprecated (lxqt-desktop-service #:key 
                                         (config 
                                          (lxqt-desktop-configuration)))
  lxqt-desktop-service-type
  "Return a service that adds the @code{lxqt} package to the system profile, and 
extends polkit with the actions from @code{lxqt-policykit}."
  (service lxqt-desktop-service-type config))


could anyone help on this matter ?