(use-modules (guix)
         (guix gexp)
         (guix store)
         (guix monads)
         (gnu packages base))

(define (aaaa)
  (gexp->script "list-files"
        #~(execl #$(file-append coreutils "/bin/ls")
             "ls")))

(run-with-store (open-connection) (aaaa))

;; prints message:
$3 = #<derivation /gnu/store/s8h94vgpg6pslzxdn7rb9ydj7hi8bgwp-list-files.drv => /gnu/store/rn0izx34ycm3k3zfzaw5blwg9sz6kzi6-list-files 7f14ad7e7d70>

;; derivation does ecists, but not the result