Access hosted json with format-param middleware

I am trying to make a very simple API using ring in clojure. I am using rack.middleware.format-params middleware to convert output to json and input from json to clojure data structures.

I have an output that works beautifully, but I can’t for the whole life access the parameters sent via json. Here is some code that works for receiving requests, but I cannot receive a POST request to return the json that it receives

(ns testing.core
  (:use [compojure.core]
        [ring.middleware.format-params :only [wrap-json-params]]
        [ring.middleware.format-response :only [wrap-json-response]]
        [ring.adapter.jetty])
  (:require [compojure.handler :as handler]))

(defroutes app-routes
  (GET "/"
       []
       {:body {:hello "world"}})

  (POST "/"
        {params :params}
        {:body params}))

(def app
  (-> (handler/api app-routes)
      (wrap-json-params)
      (wrap-json-response)))

It just returns this: {}

What am I doing wrong?