In this chapter, we learned how service workers can turn our applications from always being online to systems where we can create truly always working applications. By saving the state, handling requests locally, enriching requests locally, and even saving requests for offline use, we are able to handle the full state of our application.

Now that we have looked at creating rich web applications from both the client side and the server side with JavaScript, we will start to take a look at some advanced techniques that we can use to create highly performant applications that we only thought were possible through native application code. We can do this by utilizing C, C++, or Rust.

However, before we get to that, one piece of application development that is often overlooked by application developers is the deployment process. In the next chapter, we will look at a way of setting up continuous integration and continuous development (CI/CD) through a popular system called CircleCI.