Performance is currently at the forefront of many, if not most, web development projects. Fortunately, modern browsers provide a wealth of performance-related information and services, which can be used to optimize page load speed and responsiveness. A primary source of such information is the aptly named Web Performance API. Dan Shappir offers an overview of the Web Performance API and shows how to best use it to extract detailed performance information. You’ll learn how to leverage the Web Performance API in conjunction with browser dev tools and use it for performance monitoring during CI, to prevent regressions, and even in production.