HipHop VM (HHVM) is a new open-source virtual machine designed for executing programs written in PHP. HHVM uses a just-in-time compilation approach to achieve superior performance while maintaining the flexibility that PHP developers are accustomed to. HipHop VM (and before it HPHPc) has realized > 5x increase in throughput for Facebook compared with Zend PHP 5.2.

HipHop is most commonly run as a standalone server, replacing both Apache and modphp.

You can install a prebuilt package or compile from source.

You can run standalone programs just by passing them to hhvm: hhvm my_script.php.

HipHop bundles in a webserver. So if you want to run on port 80 in the current directory:

sudo hhvm -m server

For anything more complicated, you'll want to make a config.hdf and run sudo hhvm -m server -c config.hdf.

We'd love to have your help in making HipHop better. If you run into problems, please open an issue, or better yet, fork us and send a pull request. Join us on #hhvm on freenode.

If you want to help but don't know where to start, try fixing some of the Zend tests that don't pass. You can run them with hphp/test/run. When they work, move them to zend/good and send a pull request.

Before changes can be accepted a Contributors Licensing Agreement (pdf - print, sign, scan, link) must be signed.

HipHop VM is licensed under the PHP and Zend licenses except as otherwise noted.