NGINX is a very popular web server which is becoming even popular than the previous king Apache. NGINX has very high performance and this makes it a perfect companion for the HHVM PHP Runtime using Fast CGI interface. NGINX and O'Reilly have teamed up to give you access to a new eBook about NGINX, A Practical Guide to High Performance, for a limited time.
Over five years ago some argued that Facebook and HipHop would make PHP a viable development option for the Enterprise. That did not happen - at least not directly. Many enterprises run Drupal and other PHP tools, but not in core mission critical tasks.
The Facebook team does rapid development cycles for HHVM. If you are running in HHVM production, you need to keep your code and environments up-to-date for security just as you would for PHP. In addition to Facebook itself - Wikipedia and many WordPress hosting platforms use HHVM. So it is definitely common enough to be a target for malicious activities.
During these first half of 2015, HHVM and PHP 7 (Beta 7.0.0 now available) have engaged in a battle to become the fastest PHP engine available.
Drupal is a very popular CMS / Framework at the moment in the world. WIth a strong community it's bound to get support for HHVM, but what is the state of it now...