client.cljs

(def cds (collection))

;; interact with database

(go
  (>! (:in cds)
    {:op :create
     :val {:title "Soft Machine Vol. 1"
           :artist "Soft Machine"
           :year 1969}})
  (>! (:in cds)
    {:op :create
     :val {:title "Marble Index"
           :artist "Nico"
           :year 1969}}))

;; listen to stream of all db events

(let [stream (subscribe (:events cds) (chan))]
  (go-loop
    (println "EVENT LISTEN:" (<! stream))))

db.cljs

(defn collection
  ([] (collection (chan)
        (chan (sliding-buffer 10)) (chan (sliding-buffer 10)) {}))
  ([in out events coll]
    (go
      (loop [coll coll cid 0 e nil]
        (when e
          (>! events e))
        (let [{:keys [op id val]} (<! in)]
          (condp = op
            :query  (do (>! out (into {} (filter f coll)))
                      (recur coll cid nil))
            :create (do (>! out cid)
                      (let [x (assoc val :id cid)]
                        (recur
                          (assoc coll cid x)
                          (inc cid) [:create x])))
            :read   (do (>! out (get coll id))
                      (recur coll cid [:read id]))
            :update (recur (assoc coll id val) cid [:update id])
            :delete (recur (dissoc coll id) cid [:delete id])))))
    {:in in
     :out out
     :events (observable events)}))