> One of my pet-peeves with C projects is that it's so often more or less "works on my machine" when written by Linux users (as a Windows and FreeBSD user it often hits you on both those platforms).

Windows users singling out Linux users for not catering to their platform. How the times change...

> you often run into systemd dependencies or other non-posix behaviors

Not a problem. POSIX is irrelevant, systemd is great and we should all be using Linux to its fullest extent. Linux has great features and there is absolutely no reason not to use them all. Nobody complains about the fact BSDs have cool things like kqueue and unveil.