HHVM no longer part of WordPress core’s testing infrastructure

WordPress has never officially supported HHVM, but since WordPress 4.0 it has been compatible, largely thanks to the efforts of @wonderboymusic in #27881 and other tickets.

Many large scale sites which switched to HHVM around 2014 have since switched to PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 5.6.20 7, and usage numbers of HHVM according to the wordpress.orgWordPress.org The community site where WordPress code is created and shared by the users. This is where you can download the source code for WordPress core, plugins and themes as well as the central location for community conversations and organization. https://wordpress.org/ update statistics indicate that HHVM powers only several dozen WordPress websites as of April 2017.

CoreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress.’s unit testunit test Code written to test a small piece of code or functionality within a larger application. Everything from themes to WordPress core have a series of unit tests. Also see regression. suite when run on HHVM never actually passed (this may not be completely accurate, memories are hazy), often errored completely, and was always marked as an allowed failure. All of this, coupled with the disproportionately high amount of effort required to maintain the test and CI infrastructure for HHVM, means that WordPress core is no longer tested on HHVM as part of the Travis CI build. See #40548 for details.

If you’re running a WordPress website on HHVM, you should consider switching to PHP 7+ which is far more widely supported and tested, and offers all of the memory and performance benefits that HHVM pushed forward.