Great work! In this chapter, we've learned a huge amount! We wrote code to connect to an XMPP server, handle incoming messages and presence subscriptions, inspect and build stanzas, and send chat state notifications.
Ultimately, we've built a useful bot that heads off and fetches information about subjects from DuckDuckGo's API. It's not hard to see how we can extend this concept to also do lots of other useful tasks, from being a highly secure calculator (because everyone needs one of those!) to being able to run commands remotely on a server based on incoming messages. The world, as they say, is your oyster!
In the next chapter, we are going to learn about a library called XMPP For The Web (XMPP-FTW), which will help us build browser-based applications including browser-based chat applications, which we will explore in subsequent chapters.