[fkorotkov]

macOS EULA has some special wording around "Permitted Developer Services" allowing more flexibility:

> Permitted Developer Services means continuous integration services, including but not limited to software development, building software from source, automated testing during software development, and running necessary developer tools to support such activities.

As for layering, Tart doesn't support it at the moment. It seems APFS is not particularly good for layering but Tart uses sparsed files when storing VMs locally. Sparsed disk image file basically "skips" zero bytes which saves a lot.