Clojure liberator example that isn't working

core.clj

(ns liberated.core
  (:require [liberator.core :refer [resource defresource]]
            [ring.adapter.jetty :refer [run-jetty]]
            [compojure.core :refer [defroutes ANY]]))

(defroutes app
  (ANY "/" [] (resource :available-media-types ["text/html"
                                                "application/json"]
                        :handle-ok (fn [_] {:foo "Hello, Internet."}))))

(defn -main []
  (run-jetty #'app {:port 3000}))