(From what I've heard, I don't know how true it is, Apple became less open with Darwin, around the time of the PPC-Intel transition, out of fear it was making life easier for people trying to use OS X on non-Apple hardware easier.)
(From what I've heard, I don't know how true it is, Apple became less open with Darwin, around the time of the PPC-Intel transition, out of fear it was making life easier for people trying to use OS X on non-Apple hardware easier.)
[1] https://opensource.apple.com/ 10.11.6 is latest macOS release at the time of writing.
Why? Without the UI and OS X GUI programs it's not something many would care to run as opposed to Linux or FreeBSD, and most haven't.
So, now I have a non-GUI app for (among other platforms) macOS, I want a build machine for compilation and automated tests. Ideally just a VM somewhere (maybe even in the cloud). To legally run macOS in such a way, it needs to run on Apple hardware, which adds expense and complexity. However, I could run a Darwin VM legally on any hardware. Now of course, Darwin isn't quite macOS, but for a non-GUI app it might be close enough (depending on exactly which APIs it uses and whether those APIs fall into the open source Darwin subset).
Is that a particularly common use case? Probably not. But there probably are multiple open source projects and maybe even some proprietary software packages for which that use case would exist.
I'm not sure if the problem is Apple or a lack of interest and community.
I'd definitely be up to trying to build it sometime in the future. I'm a little busy at the moment. I'd expect it to take a few days at least based on my experience with Linux from scratch.