Read Twitter direct messages and check messages for links
Your get-url function could just use get-in:

(defn- get-url [message]
  (get-in message [:entities :urls 0 :expanded_url]))


links-from-direct-messages has quite a lot of nested calls.  When you've got a bunch of nested operations like that it can be nice to re-write them using one of the threading macros (-&gt; and -&gt;&gt;).  These take an input, and then "thread" it through a series of forms as the first (in the case of -&gt;) or last (in the case of -&gt;&gt;) argument.  By doing this, they allow you to rewrite nested calls sequentially.

This is mentioned in the style guide you linked.

In the case of links-from-direct-messages you're calling map and filter, which both accept the collection as their last argument, so you can use -&gt;&gt;:

(defn links-from-direct-messages []
  (-&gt;&gt; (direct-messages :oauth-creds oauth-credentials)
       :body
       (filter trusted-user?)
       (filter has-url?)
       (map get-url)))