duck1123/jiksnu

Consider using:

(.then
  (get-app-data)
  (fn [data]
    (let [username (.-user data)]
      (js/console.log "Username: %s" username)
      username)))

instead of:

(-> (get-app-data)
 (.then
   (fn [data]
     (let [username (.-user data)]
       (js/console.log "Username: %s" username)
       username))))