Ejabberd
Ejabberd is an open-source, high-performance XMPP (Extensible Messaging and Presence Protocol) server written in Erlang. It enables real-time messaging, presence, and collaboration features for applications, supporting features like multi-user chat, file transfer, and voice/video calls. It is widely used for building scalable instant messaging systems and chat applications.
Developers should learn Ejabberd when building real-time communication applications that require robust, scalable messaging infrastructure, such as chat apps, IoT device communication, or enterprise collaboration tools. It is particularly valuable for projects needing XMPP compliance, high concurrency handling, and integration with other services via its modular architecture.