Deno 1.4, released September 13, is being called the largest feature release yet. Highlights include a web standard WebSocket API, for communicating with remote servers via the WebSocket protocol, and an integrated file watcher that can be used to restart any script when its dependencies change. To use the file watcher, developers run a script as they normally would but add the
--watch flag. The
unstable flag also must be used because this feature is not yet stable.