I had never heard of NextBSD. FreeBSD kernel with hooks to some of Apple's services on MacOS.

... For us, one of the more interesting projects was #NextBSD, which went the other way. It kept the #FreeBSD kernel, but modified it so that it could use some of Apple's higher-level code, such as launchd, Apple's next-generation init system. In other words, Cupertino's equivalent of systemd....

[1]https://www.theregister.com/2024/10/11/macos_15_is_unix/
[2] https://github.com/NextBSD/NextBSD

Success. #NextBSD with #launchd is running

cc @mmokhi