A web platform API that allows script to asynchronously acquire a lock over a resource, hold it while work is performed, then release it. While held, no other script in the origin can aquire a lock over the same resource. This allows contexts (windows, workers) within a web application to coordinate the usage of resources.

Participate: GitHub issues — Docs: MDN — Tests: web-platform-tests

• The Explainer is a developer-oriented preview of the API.
• The Specification is for browser implementers.