Apple took a fundamentally different approach to virtualisation when it transitioned to Arm-based Macs. Rather than relying on third-party solutions like VMware and Parallels, Apple built virtualisation directly into macOS starting with Monterey. This architectural decision was driven by necessity—every hardware device in an Apple silicon chip differs from its Intel equivalent, making it impractical for external developers to create comprehensive device drivers.

The solution uses Virtio, a standard that abstracts I/O devices and allows the guest operating system to communicate with host hardware through paravirtualised drivers. This approach shifts device support responsibility from virtualiser vendors to Apple itself, guaranteeing optimal performance but also giving Apple control over what hardware and features are supported. Linux already had strong Virtio support, so Apple's engineers spent years building that capability into macOS before Monterey's release.

Performance benchmarks show the approach works well. Geekbench 6.3.0 results for Monterey running as both guest and host showed CPU single-core scores of 3,643 versus 3,892, and GPU Metal scores of 102,282 versus 110,960. However, significant limitations remain: App Store apps won't run since VMs can't be signed in, iCloud support requires both guest and host on Sequoia, and network connections are restricted to Ethernet despite Wi-Fi connectivity being available through the host.

Apple's license permits up to two simultaneous macOS virtual machines for software development, testing, or personal use. This enables practical scenarios like running older macOS versions for compatibility testing, isolating potentially malicious software, or accessing different iCloud accounts simultaneously.