Coding With David

As .NET developers, our instinct when dealing with concurrency is to look at the backend: optimistic locking in Entity Framework, Redis distributed locks, or background queue orchestration. We rarely think about client-side concurrency until a user opens our application across three separate browser tabs. Suddenly, all three tabs trigger a local cache warmup, attempt to flush an IndexedDB offline queue simultaneously, and trigger duplicate background sync calls. Before building an ad-hoc coordination protocol over localStorage events or BroadcastChannel, look at what the browser already provides: the Web Locks API (navigator.locks). How Web Locks Work The Web Locks API acts as an origin-wide mutex across tabs, windows, and Web Workers. Instead of managing lock acquisition and manual teardown, you pass a callback to navigator.locks.request(). The browser grants the lock, executes your async callback, and releases the lock the moment the returned promise resolves or rejects. JavaScript a...