UTM is a cross-platform emulator that allows you to run macOS, Windows, or Linux. Here's how to use it to run very old versions of Apple's Mac operating system.

You can also easily run Linux on your older Intel-powered Mac or, with more effort, run Asahi Linux on M-powered Macs. Apple Container is written in Swift and licensed under Apache 2.

UTM is an emulator for virtualizing other operating systems. Here's how to use it to run Apple's Mac OS 9 on a Mac running on Apple Silicon.