steipete/vz

The vz project lets developers write programs in the Go language that create and run virtual machines on Mac computers. A virtual machine is essentially a computer-within-a-computer, allowing you to run an entirely different operating system, like Linux or a separate copy of macOS, in a window or background process. This tool bridges the gap between Go and Apple's own built-in technology for managing these virtual machines, making it easier for developers to build Mac apps that need to run other operating systems. Instead of relying on third-party virtualization software, this library taps directly into Apple's native Virtualization framework. At a high level, it translates a developer's Go code into the underlying Apple commands that boot up a Linux or macOS system. The tool handles the setup for things like storage, networking, and shared folders. It also supports running Intel-based applications on Apple Silicon Macs using Apple's translation layer, allowing older software to run smoothly inside the newer virtual environment. Who would actually use this? Software teams building Mac applications that need to run or test software in a contained Linux environment. For example, a developer building a tool similar to Windows Subsystem for Linux might use this to launch a lightweight Linux system directly from their Mac app. It is also useful for automated testing setups where a program needs to spin up a clean Linux instance, run some code, and shut it down. The README notes that real projects like Lima (which provides automatic file sharing and port forwarding) and vfkit (a command-line tool for managing virtual machines) rely on this library. There is a notable tradeoff in how the project is built: because it taps into Apple's native frameworks, it requires a specific setup. Developers must apply a special security entitlement to their applications, proving to the system that the software has permission to create virtual machines. Additionally, the library can only access certain Apple features if the developer is using a recent version of Apple's developer tools, meaning older build environments will miss out on newer functionality.