i. What You Need

To follow along with this book, you’ll need the following:

• A Mac running the latest macOS. This is so you can install the latest version of the required development tool: Xcode.
• Xcode 11 or later Xcode is the main development tool for writing code in Swift. You need Xcode 11 at a minimum, since that version includes Swift 5.1. You can download the latest version of Xcode for free from the Mac App Store, here: apple.co/1FLn51R.

If you haven’t installed the latest version of Xcode, be sure to do that before continuing with the book. The code covered in this book depends on Swift 5.1 and Xcode 11 — you may get lost if you try to work with an older version.