[skissane]

> Wasn’t compatibility what really sunk WSL1?

Yes, but a big part of the problem with WSL1 was the size of the conceptual gap between POSIX and Windows NT that WSL1 had to bridge. An “MSL1” would likely have fewer problems because the gap between macOS and Linux is smaller, given they are both POSIX

The other thing Apple could potentially do, is add Linux-compatible APIs to macOS. IBM wanted to support Kubernetes on their z/OS mainframe operating system, so they implemented on it a clone of Linux namespace APIs, e.g. unshare. Then we could have macOS nodes in a K8S cluster-which might actually be useful for some people, e.g. if you have a Jenkins CI farm, the Linux nodes can run on K8S, but currently macOS nodes (which you need if you are targeting iOS or macOS) can’t, they have to be bare metal or VMs.

More Linux-macOS source compatibility would also benefit macOS by making it less work to port software to it from Linux

[qalmakka]

Linux and the BSDs take APIs one from the other all of the time. The issue with having a Linux ABI is that you don't need just the few APIs you're missing, you need to implement the WHOLE Linux API and it has to be _perfect_, otherwise stuff will randomly break. I loved the original WSL, I had to use it for a time period back in the day when I was stuck on a Windows PC, but it can't be denied it was full of random bugs

[cogman10]

The original WSL proves that you actually don't need to be perfect or to have the entire ABI to be pretty useful.

It's true that missing ABIs will cause random crashes and problems. However, a lot of apps can run with a minimal set of ABIs.