It may have all that you need, but that sweeping generalization is far from true for everyone. For example, things that I need that it does not have (last that

It may have all that you need, but that sweeping generalization is far from true for everyone. For example, things that I need that it does not have (last that I checked) include: filesystem-neutral nmount(), POSIX RT signals, the "new" 1990s dynamic PTY allocation system, a KDGETMODE ioctl on wscons, waitid(), fexecve(), and ACLs. And then there are the things that would make life easier to not have to bodge around: const-correct ncurses API (available in ncurses since 1997), const-correct login_cap API, const-correct sysctl(), and no multiple evaluations in EV_SET(). It would be very welcome for it to gain all of these, but until then there is no "it has all that you need" realization on the cards.