The HHVM project has announced
that the Hack language and PHP will truly be going separate ways. The HHVM
v3.30 release, due by the end of the year, will be the last to support code
written in PHP. “Ultimately, we recommend that projects either
migrate entirely to the Hack language, or entirely to PHP7 and the PHP
runtime.” HHVM was first announced
in 2011 as a compiler for the PHP language.