I see great advantages to offering a POSIX compatibility layer. It can be sand-boxed to the app's context instead of making it a system wide dependency. Getting

I see great advantages to offering a POSIX compatibility layer. It can be sand-boxed to the app's context instead of making it a system wide dependency. Getting existing apps to run out of the box, and then convincing them to adapt a leaner, narrower set of system calls is probably more valuable than requiring from-the-scratch development.