Stoyan Stefanov is a Facebook engineer, author, and speaker. He talks regularly about web development topics at conferences and his blog www.phpied.com, and also runs a number of other sites, including JSPatterns.com—a site dedicated to exploring JavaScript patterns. Previously at Yahoo!, Stoyan was the architect of YSlow 2.0 and creator of the image optimization tool Smush.it.

A "citizen of the world", Stoyan was born and raised in Bulgaria, but is also a Canadian citizen, currently residing in Los Angeles, California. In his offline moments, he enjoys playing the guitar, taking flying lessons, and spending time at the Santa Monica beaches with his family.

Kumar Chetan Sharma studied to be an electronics engineer and has always wanted to build an ultimate sound system. He then, by chance, got a part time job as a trainee HTML guy. From there he picked up CSS and JavaScript and there was no looking back. It was the time when JavaScript was used to validate forms or create fancy DHTML effects and IE6 was the only browser the world knew. He has been developing web applications since then, using LAMP stack. He has worked on white label social networking applications to web control panels for telecom and networked electrical charger infrastructures. He currently works as a frontend engineer for Yahoo! Search.