As many tools and technologies will be covered, we recommend using IntelliJ IDEA as the tool for code development. The main reason is that this integrated development environment (IDE) works without any tedious configuration. The Community Edition (IntelliJ IDEA CE) comes with a bunch of built-in features and plugins that make coding easy and efficient. It automatically recommends plugins that can be installed depending on the file extension. As IntelliJ IDEA is the choice we made for this book, you will find references and steps referring to its actions or menus. Readers should find a proper way to emulate those steps if they are using other IDEs. Refer to: https://www.jetbrains.com/idea/ for instructions on how to download and install IntelliJ IDEA.