HHVM is an open-source virtual machine designed for executing programs written in Hack. HHVM uses a just-in-time (JIT) compilation approach to achieve superior performance while maintaining the development flexibility that PHP provides.
HHVM is intended for Hack projects, and also supports a large subset of PHP 7 that is required by common tools and libraries. We no longer recommend using HHVM for purely PHP projects.
If you're new, try our getting started guide.
You can run standalone programs just by passing them to hhvm:
If you want to host a website:
- Install your favorite webserver. Proxygen is built in to HHVM, fast and easy to deploy.
- Install our package
- Start your webserver
sudo /etc/init.d/hhvm start
- Visit your site at
Our getting started guide provides a slightly more detailed introduction as well as links to more information.
We'd love to have your help in making HHVM better. If you're interested, please read our guide to contributing.
HHVM is licensed under the PHP and Zend licenses except as otherwise noted.
See Reporting Crashes for helpful tips on how to report crashes in an actionable manner.
Reporting and Fixing Security Issues
Please do not open GitHub issues or pull requests - this makes the problem immediately visible to everyone, including malicious actors. Security issues in HHVM can be safely reported via HHVM's Whitehat Bug Bounty program:
Facebook's security team will triage your report and determine whether or not is it eligible for a bounty under our program.
There is also a FAQ for contributors to HHVM.