Steve Steve Souders works at SpeedCurve on the interplay between performance and design. He previously served as Google’s head performance engineer, chief performance Yahoo!, and as chief performance officer at Fastly. Steve has pioneered much of the work in the world of web performance. He is the author of High Performance Web Sites and Even Faster Web Sites. He is the creator of many performance tools and services including YSlow, the HTTP Archive, Episodes, ControlJS, and Browserscope. Steve taught CS193H: High Performance Web Sites at Stanford University and serves as co-chair of Velocity, the web performance and operations conference from O’Reilly.