High Performance Web Sites

Foreword

You're lucky to be holding this book. More importantly, your web site's users are lucky. Implement even a few of the 14 techniques Steve shares in this groundbreaking book and your site will be faster immediately. Your users will thank you.

Here is why it matters. As a frontend engineer, you hold a tremendous amount of power and responsibility. You're the users' last line of defense. The decisions you make directly shape their experience. I believe our number one job is to take care of them and to give them what they want—quickly. This book is a toolbox to create happy users (and bosses, too). Best of all, once you put these techniques in place—in most cases, a one-time tweak—you'll be reaping the rewards far into the future.

This book will change your approach to performance optimization. When Steve began researching performance for our Platform Engineering group at Yahoo!, I believed performance was mainly a backend issue. But he showed that frontend issues account for 80% of total time. I thought frontend performance was about optimizing images and keeping CSS and JavaScript external, but the 176 pages and 14 rules you're holding in your hand right now are proof that it's much more.

I've applied his findings to several sites. Watching already-fast sites render nearly twice as quickly is tremendous. His methodology is sound, his data valid and extensive, and his findings compelling and impactful.

The discipline of frontend engineering is still young, but the book in your hands is an important step in the maturation of our craft. Together we'll raise expectations about the Web by creating better and faster (and therefore more enjoyable) interfaces and experiences.

Cheers to faster surfing!

–Nate Koechley

Senior Frontend Engineer Yahoo! User Interface (YUI) Team, Platform Engineering, Yahoo! Inc. San Francisco, August, 2007