Stoyan Stefanov

Stoyan Stefanov
Web developer, Facebook

Website | @stoyanstefanov

Stoyan Stefanov (, @stoyanstefanov) is a front-end engineer at Yahoo! Search. Creator of the online image optimization tool and architect of YSlow 2.0. Book author (Object-Oriented JavaScript) and contributor (Even Faster Web Sites, High-Performance JavaScript) and speaker (Velocity, Ajax Experience, JSConf).


Keynotes Ballroom ABCD
Andreas Grabner (Dynatrace), John J. Barton (IBM), Stoyan Stefanov (Facebook), Bryan McQuade (Google)
Average rating: ***..
(3.58, 45 ratings)
Demos from dynaTrace, Firebug, YSlow, and Page Speed. Read more.
Stoyan Stefanov (Facebook)
Average rating: ***..
(3.40, 48 ratings)
Running PageSpeed - all checks. YSlow - A. So what's next to do? Well, you can cheat! You know that time is relative - one hour with your mother-in-law feels much longer than one hour on the beach. The same way you can bend the perception of the page loading time and make the page feel faster, even though the RTT is the same. Read more.
Web Performance Ballroom AB
Nicole Sullivan (Stubbornella), Stoyan Stefanov (Facebook)
Average rating: ****.
(4.76, 29 ratings)
Your website has out-of-control CSS bloat. You know your performance is being impacted, but how do you move from organic CSS with no particular architecture to something lighter, more logical, and easier to maintain? In this session, Nicole Sullivan and Stoyan Stefanov will show you how they improved the CSS at Facebook and Yahoo! Search. Read more.

For Velocity China sponsorship information for companies outside China, contact Yvonne Romaine at

  • Google
  • Strangeloop
  • Yahoo! Inc.
  • Dyn Inc.
  • Facebook
  • Schooner Information Technology
  • Tilera
  • AlertSite
  • AppDynamics
  • Aptimize
  • CDNetworks
  • Circonus
  • Cloudscaling
  • Clustrix
  • Coradiant
  • Dell
  • DTO Solutions
  • MaxiScale
  • Neustar
  • Nokia
  • NorthScale, Inc.
  • Shopzilla
  • Splunk
  • Virident
  • Zoompf
  • Neustar

For information on exhibition and sponsorship opportunities at the conference, contact Yvonne Romaine at

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