You're going to need a Business Central sandbox, and it has to be an online Business Central one for this recipe. If you need help, then you can always refer to the Setting up your development sandbox recipe in Chapter 1, Let's Get the Basics Out of the Way, for information on how to set all of this up. If you've already been installing apps in your sandbox, then you can remove them all or simply delete that sandbox and create a new one.

You also need to download ch9/8-installing-tenant-customization/Default publisher_ALProject1_1.1.0.0.app from the GitHub link at the start of this chapter.