Facebook has won over the hearts and minds of the PHP community with HipHopVM, their new runtime made available to the world. HHVM boasts speed runtime boosts for PHP developers, plus it enables them to take advantage of types if they convert their code to Hack. It's not in wide production use yet (outside of Facebook), but the rate of adoption is much higher than any release of core PHP has ever been.

But fast is never fast enough for the internet. Developers have turned to C for writing PHP extensions to boost speed, allowing expensive functions to be executed in a highly optimized way. But the process of writing these extensions is rather unpleasant, especially if you have to touch PHP internals at a deep level.

Building an extension to HHVM is much easier than writing a PHP extension thanks to its modern development practices, clean codebase, and lack of a "design by committee" roadmap. Plus, you can even use PHP code in extension definitions directly! However, there are still some pitfalls related to the fast speed of development, small community, and limited documentation. I'll teach you all about how to bypass those as we explore how to build a HHVM extension, focusing on performance monitoring (the space my company is in).