gistfile1.clj

(let [rs (resource-agent (:url account))
      a (model-agent (:foreign-key (meta rs) id model))] 
  (add-watch rs (:id (meta a))
                   (fn [k ref old-state new-state]
                     (when (empty? (clojure.set/intersection @a new-state))
                       (reset! a (select #(= (:id (meta a)) (:id %)) new-state)))))
  (add-watch a :update
                (fn [k ref old-state new-state]
                     (when (empty? (clojure.set/intersection @rs new-state))
                       (send rs #(-> %
                                     (disj (first old-state))
                                     (conj (first new-state))))))))