Hands-On JavaScript High Performance

Fast web applications are shaped by decisions at many layers—not just by a clever line of JavaScript. In Hands-On JavaScript High Performance, Justin Scherer moves between browser-side techniques and server-side tools to examine how those pieces fit together, with practical examples along the way.

The book takes readers from performance inspection and modern JavaScript into Svelte,, streams, workers, and WebAssembly. Its broad scope makes it a useful exploration for developers interested in understanding performance across the web stack rather than treating the browser and server as separate worlds.

Start by measuring the browser

The opening chapters introduce browser developer tools and benchmarking, including Chrome’s performance, memory, and rendering tools. From there, Scherer considers the balance between immutability and mutability, then reviews modern JavaScript features and browser APIs. That early focus on inspection and trade-offs gives readers context for the implementation topics that follow.

Build with JavaScript, Svelte, and

Practical examples include a Todo application and a weather application using Svelte and vanilla JavaScript, followed by a shift into and server-side development. The book explores modules, networking, message passing, and streams, including non-blocking I/O and custom stream implementations.

Explore the wider web stack

Further topics include data formats beyond JSON, building a static server, dedicated and shared workers, service workers, and WebAssembly. Together, these chapters offer a broad tour of techniques for client-side and server-side JavaScript development, with attention to how application structure and browser capabilities relate to performance.

Who may find it useful

This book is suited to web developers who already have a working grasp of JavaScript and want to investigate performance tools, modern browser features, and server-side techniques. Readers looking for a single, focused deep dive into just one framework may find its wide-ranging approach less specialized; its strength is the view across multiple parts of web development.