Web applications frequently need to open a channel of communication with a server to get real-time updates. This is often done using two-way communication via WebSockets, but they can be complex to implement and, in many cases, are overkill. Server Sent Events (SSEs) offer an easy-to-implement alternative for many common use cases where an application only needs to receive updates.

In this session, we'll explore what the SSE spec is and how to implement it in a web application using JavaScript. We'll also take a quick look at a number of open source libraries LaunchDarkly maintains for implementing SSEs in Python, .NET, Go and more for server-to-server SSEs.