mqqt.clj

;; I would be very surprised if it works...
(go
  (loop []
      (let [c (chan)
            tok (do
                  (reify MqttCallback
                    (deliveryComplete [_ tok]
                      (when-let 1
                        (go (>! c :arrived))
                        (swap! tok->chan dissoc tok))))
                  (mqtt-publish client "sneezing" "[80 m/s]"))]
          (swap! tok->chan assoc tok c)
          (when-not (alts! c (timeout 10000))
            (recur)))))