echo bot on twitter in Common Lisp

echo-bot.lisp

(ql:quickload :chirp)

(setf chirp:*oauth-api-key* "Put"
      chirp:*oauth-api-secret* "your"
      chirp:*oauth-access-token* "credencials"
      chirp:*oauth-access-secret* "here!")

(print (chirp:account/verify-credentials))

(defun status-text-without-mention (status)
  (chirp:replace-entities status (list :user-mention (lambda (x) ""))))

(defun user= (user1 user2)
  (eq (chirp-objects:id user1) (chirp-objects:id user2)))

(defun start ()
  (loop
    with time = (local-time:now)
    with last-id = nil
    for mentions = (chirp:statuses/mentions-timeline :since-id last-id)
    do (loop
         for mention in mentions
         when (local-time:timestamp<= time (chirp-objects:created-at mention))
         unless (user= (chirp:account/self) (chirp-objects:user mention))
         do (print mention)
            (chirp:reply mention (status-text-without-mention mention)))
       (when mentions
         (setf last-id (apply #'max (mapcar #'chirp-objects:id mentions))))
       (sleep (* 60 (/ 15 75)))))