Stoyan has recently joined Etsy as a web performance consultant (formerly at Facebook, WebPageTest and Yahoo!). He has a storied history as an accomplished author ("JavaScript Patterns", "React: Up and Running"), contributor, and custodian of the well-known and respected Planet Performance calendar. He habitually speaks about web development topics at conferences and on his blog at phpied.com. Stoyan is also the creator of the smush.it image optimization tool, YUI contributor and was the architect of Yahoo's performance optimization tool YSlow 2.0.