So it’d be cool if this or a sandbox tool could help.
Super interesting that they're using swift. Does this mean the project is only a wrapper for system libraries ? I can't imagine writing low-level system code in swift yet.
The container CLI tool wraps the underlying Containerization framework, which in turn vends packages for things like EXT4 file system support -- all written in Swift. Here's one example as a jumping off point. https://github.com/apple/containerization/blob/main/Sources/...
This project is very similar to docker with a background daemon server that you control via a cli to launch Linux containers.
Because Linux containers need Linux namespaces, each container is run in a virtual machine with a Linux kernel.
apple.github.io/container/documentation/