James Titcumb (@asgrim): Founder of the UK based PHP Hampshire user group and the PHP South Coast Conference. He's also a Zend Certified Engineer and consultant at Roave
Diving into HHVM Extensions:
HHVM is currently gaining popularity at quite a pace, and it's a pretty exciting time for PHP runtimes. Have you ever wondered what is going on beneath this slick and super-speedy engine? I wondered that myself, so I dived into the internals of HHVM, discovering a treasure trove of awesome stuff. In this talk, I'll show you how HHVM itself works with a guided tour of the codebase, demonstrating how it all pieces together. I'll also show you a couple of ways to write your own incredible HHVM extension. You don't need to know C++ to understand this talk - just PHP language knowledge is enough.
Marco Pivetta (@Ocramius): Software Consultant at Roave, Doctrine core team member & ZF2 contributor
Extremely defensive PHP:
What if I told you that your carefully designed and tested code was fragile? What if I told you that you can trust nobody? What does "fragile" even mean? We are going to look at fragile code, fix it, and lastly learn about various Poka-Yoke techniques that make our code very hard to break.