Fomus

(fomus
 :output '(:lilypond :view t)
 :filename "test.xxx"
 :verbose 1
 :global (list (make-timesig :off 0 :time '(5 8) :div '(3/2 1) :props '((:keysig :dmaj))))
 :auto-cautionary-accs t
 :parts
 (list
  (make-part
   :name "Piano"
   :instr '(:piano :simultlim 1)
   :events
   (loop
    for off from 0 to 8 by 1/2
    collect (make-note :off off
               :dur (if (< off 10) 1/2 1)
               :note (+ 48 (random 25)))))))