In this chapter, we created the last part of our project using functional reactive programming; here we used a lot of the knowledge from the other parts of this book, such as using functional reactive programming in the browser, creating observables from user inputs, using several different operators, modeling messages and connections as observables, subscribing to an observable, buffering data from an observable to process it in batch, and creating simple tests for the frontend application.
We did not use all of the knowledge we learned throughout this book, because it is hard to find a sample application which uses everything, and while keeping it simple enough to use as an example inside a book.
Keep in mind that this knowledge is important and can be used in other programs in your day to day work.