In-depth articles, tutorials, and guides on Web APIs & Async — covering everything from fundamentals to advanced patterns.
SharedArrayBuffer is the only browser primitive that allows multiple JavaScript contexts to read and write the same memory simultaneously. Combined with Atomics, it enables lock-free synchronization for high-performance parallel computation in the browser.
Web Workers and Service Workers both run JavaScript off the main thread, but they serve fundamentally different purposes. Understanding when to reach for each one — and when not to — is key to building performant, reliable web applications.
Every fetch request you fire without a cancellation mechanism is a potential source of race conditions, memory leaks, and stale state. AbortController is the standard browser API that solves this — and it is simpler than most developers realise.
JavaScript is single-threaded, yet it handles timers, network requests, and user input concurrently without freezing. The event loop is the mechanism that makes this possible — and understanding macrotasks vs microtasks explains the execution order that trips up almost every developer at some point.