From the article: "The Lua standard library uses the POSIX C library, making it portable; but that also means that you can’t use sockets, it doesn’t support signals or timers, and all OS calls block the thread. Using the POSIX C library is like going backwards in time."

I can't speak to the "Lua standard library" but I can say that I believe every single statement above about the POSIX C standard is incorrect as written.

POSIX Sockets: http://man7.org/linux/man-pages/man2/socket.2.html

POSIX Signals: http://man7.org/linux/man-pages/man7/signal.7.html, http://pubs.opengroup.org/onlinepubs/009695399/functions/sig...

POSIX Timers: http://www.2net.co.uk/tutorial/periodic_threads, http://pubs.opengroup.org/onlinepubs/009695399/functions/tim...

Nonblocking IO: http://man7.org/linux/man-pages/man7/aio.7.html

That doesn't mean that the POSIX features are best in class or easy to use -- rather just that the features exist.