server.lisp

(defun server ()
  (zmq:with-context (ctx)
    (zmq:with-socket (socket ctx :rep)
      (zmq:bind socket "tcp://127.0.0.1:5555")
      (loop
         (let ((query (make-instance 'zmq:msg)))
           (zmq:recv socket query)
           (let ((req-string (zmq:msg-data-as-string query)))
             (format t "Recieved message: '~A'~%" req-string)
             (zmq:send socket (make-instance 'zmq:msg :data req-string)) ))))))

(server)