Congratulations! Finally, we are here. Welcome to the last chapter of the second section of this book! At this point, we are really sure that you know how to plan and develop, and now we will add some cool features to make our application more interesting and scalable. Maybe you were thinking about how to share some properties or trigger events across all the components, or make your application understandable for people from different countries speaking different languages. Well, internationalization is a great concept that you are going to meet in this chapter. What if you need to perform operations to convert dates, numbers, or currency? Well, these kinds of situations (and so much more) are very common in a real application, so you need to be prepared to deal with it. You know what? We have good news! Aurelia is prepared with a great solution for every case (and so much more too!). In this chapter, you will learn the following topics:

• Event Aggregator
• Internationalization
• Logging
• Aurelia dialog
• Value converters
• Custom binding behaviors
• Validators
• Custom attributes
• Computed properties

Let's start with this awesome chapter; I assure you that you will find it very useful and interesting. We promise.