Now touchpad and my config work, xserver is compiling, an other issue with touchpad configuration was solved in Help Guix maillist.

Here it is my config:

;;this is znavko's cute config

(use-modules (gnu) (gnu system nss)
             (gnu system locale) ;;for locale-definition
             (gnu services desktop)
             ;;(gnu services dns) ;;for dnsmasq
             (srfi srfi-1) ;;for remove function
             (gnu services networking) ;;for remove ntp
             (gnu services avahi) ;;for remove avahi
             (gnu services xorg)
             ;;(gnu services databases);;for postgres
             (gnu packages admin) ;;for wpa_supplicant
)
(use-service-modules desktop)
(use-package-modules certs gnome)

;;(define %redundant-linux-modules '("pcspkr" "snd_pcsp"))

(operating-system (host-name "antelope") (timezone "Europe/Moscow") (locale "en_US.utf8")
  (bootloader (bootloader-configuration
                (bootloader grub-bootloader)
                (target "/dev/sda")))
  (file-systems (cons (file-system
                        (device "/dev/sda1") (mount-point "/") (type "ext4"))
                      %base-file-systems))
  (swap-devices '("/dev/sda2"))

  (users (cons* (user-account (name "bob") (group "users")
                (supplementary-groups '("wheel" "netdev" "audio" "video"))
                (home-directory "/home/bob"))
                (user-account (name "alice") (group "users")
                (supplementary-groups '("wheel" "netdev" "audio" "video"))
                (home-directory "/home/alice"))
                (user-account (name "mom") (group "users")
                (supplementary-groups '("wheel" "netdev" "audio" "video"))
                (home-directory "/home/mom"))
               %base-user-accounts))

  ;; This is where we specify system-wide packages.
  (packages (cons* nss-certs         ;for HTTPS access
                   gvfs              ;for user mounts
           wpa-supplicant
           isc-dhcp
                   %base-packages))

  (services (cons*  
                    ;;(service postgresql-service-type)
                    (service xfce-desktop-service-type)
                    (modify-services      
                      ;;(remove (lambda (service)
                      ;;  (eq? (service-kind service)
                      ;;    wpa-supplicant-service-type))
                      ;;  (remove (lambda (service)
                      ;;    (eq? (service-kind service)
                      ;;      static-networking-service-type))
                          (remove (lambda (service)
                            (eq? (service-kind service)
                              ntp-service-type))
                            (remove (lambda (service)
                              (eq? (service-kind service)
                                avahi-service-type))
                              (modify-services %desktop-services

                                (slim-service-type config =>
                                              (slim-configuration
                                               (xorg-configuration
                                                 (xorg-configuration
                                                  (extra-config
                                                  
'("Section \"InputClass\"
        Identifier \"touchpad\"
        Driver \"libinput\"
        MatchIsTouchpad \"on\"
        Option \"Tapping\" \"on\"
EndSection")
                                 )))))
  )  ;end of modify-services 2nd


                            )  ;end of remove avahi
                          )  ;end of remove2 ntp
                        ;;)  ;end of remove3 networking
                      ;)  ;end of remove4 wpa-supplicant
                      (elogind-service-type
                        c => (elogind-configuration (handle-lid-switch 'ignore)))
                    );;end of modify-services 1st desktop-services
  ));;end of services

  ;; Allow resolution of '.local' host names with mDNS.
  (name-service-switch %mdns-host-lookup-nss)


 (kernel-arguments '("modprobe.blacklist=pcspkr,snd_pcsp"))
 ;(kernel-arguments
 ;    (list (string-append "modprobe.blacklist="
 ;                         (apply comma-separated
 ;   %redundant-linux-modules))))

);;end of operating-system

 
I hope I'll be able to configure networking with wpa_supplicant + dhclient only, without newtworkmanager (that I hate) as I asked before
https://lists.gnu.org/archive/html/help-guix/2018-11/msg00208.html <https://lists.gnu.org/archive/html/help-guix/2018-11/msg00208.html>

Now I cannot determine what to type to remove networkmanager and let autostart wpa_supplicant  dhclient with my cute wpa_supplicant.config?

Mar 29, 2019, 4:16 PM by ludo@gnu.org:

> Ricardo Wurmus <> rekado@elephly.net <mailto:rekado@elephly.net>> > skribis:
>
>> znavko@tutanota.com <mailto:znavko@tutanota.com>>>  writes:
>>
>>> `guix pull` fail on building xserver derivation. log is attatched.
>>>
>>
>> Backtrace:
>>  3 (primitive-load "/gnu/store/fdp2jmpz6pwdlmdg1izih8cly75?")
>> In ice-9/ports.scm:
>>  462:17  2 (call-with-output-file _ _ #:binary _ #:encoding _)
>> In srfi/srfi-1.scm:
>>  637:5  1 (for-each #<procedure 61d180 at ice-9/eval.scm:333:13 ?> ?)
>> In unknown file:
>>  0 (scm-error wrong-type-arg "for-each" "Wrong type argum?" ?)
>>
>> ERROR: In procedure scm-error:
>> In procedure for-each: Wrong type argument: "Section \"InputClass\"\n        Identifier \"touchpad\"\n        Driver \"libinput\"\n        MatchIsTouchpad \"on\"\n        Option \"Tapping\" \"on\"\nEndSection"
>>
>> This is an error in your operating system configuration.  You provided a
>> string, but the error shows that a list is expected.
>>
>
> znavko, could you share your OS config?
>
> Thanks,
> Ludo’.
>