Building a Better Web
June 19–20, 2017: Training
June 20–22, 2017: Tutorials & Conference
San Jose, CA

Reverse engineering Amazon and the Guardian

David Fox (LookZook)
9:00am–9:40am Wednesday, June 21, 2017
Fullstack Development
Location: 210 CG
Secondary topics:  Designing for performance, Mobile, UX optimization
Average rating: ****.
(4.67, 6 ratings)

Who is this presentation for?

  • Web developers and performance engineers

Prerequisite knowledge

  • Intermediate knowledge of CSS and JavaScript

What you'll learn

  • Gain a strong foundation of how browser internals work
  • Learn how to utilize this knowledge to make faster and more enjoyable web pages for mobile and desktop


Despite spending countless hours optimizing our own sites, many of us still look at sites like Amazon’s or the Guardian’s in awe, wondering how they are still so much more performant. What are they doing differently? David Fox reverse engineers these sites, shedding light on the various tricks and optimizations they have and we don’t.

The reason why these sites are so performant is simpler than you might think: the companies just have a really good understanding of how the internals of browser engines like WebKit, Blink, Gecko, and Trident work on desktop and mobile. And because of that knowledge, these companies are able to design optimally and use a multitude of tricks and optimizations we don’t.

Topics include:

  • How to help the browser progressively load your page
  • Avoiding the flash of invisible or unstyled text when using web fonts
  • Preventing your pages from “hopping” around while loading, making them easier to read
Photo of David Fox

David Fox


David Fox is CTO and founder of LookZook—a company providing highly visual web performance metrics for developers and CMOs. David got his start in programming and UX as a Flash game developer during the golden age of Flash gaming (remember Newgrounds?). Since then he’s applied that knowledge and transitioned to the web: becoming a Blink contributor, speaker, and writer for various blogs like the annual Performance Calendar. In his free time, David enjoys reading about psychology, cooking, playing video games, and beating his friends at poker.