Comment by userbinator

Several years ago I remember making something that could be considered a custom "distro" of macOS that would be VM-oriented and as minimal as it could be for CI purposes, by starting with the recovery/installer partition and adding what I needed while deleting what I didn't. Not surprisingly, there was next-to-no precedent of such that I could find, and my biggest source of information was the Hackintosh community. Nonetheless it was not too difficult, if tedious, to do so, and the final disk image size I arrived at was less than 1GB. In general the macOS community is, to put it bluntly, mostly computer-illiterate non-power-users who will either advocate against you or otherwise have no idea what you're talking about. In contrast there's a HUGE amount of existing information on modding Windows, and of course Linux sits at the other extreme.