EMQX

The platform implements the MQTT protocol suite (v5.0, v3.1.1, v3.1) and additional IoT protocols such as MQTT‑SN, CoAP, LwM2M, and MQTT over QUIC, allowing devices to publish and subscribe to topics with sub‑millisecond latency. It can be deployed as a self‑hosted cluster that scales to over one hundred million concurrent connections and processes millions of messages per second, while providing master‑less clustering for high availability and fault tolerance. A built‑in SQL‑based rule engine enables real‑time transformation, enrichment, and filtering of in‑flight data, and the system includes gateways for bridging to more than fifty external services, including message queues, databases, and cloud platforms.

Target users are developers and operators of large‑scale IoT, industrial IoT, connected vehicle, and AI‑driven data pipelines that need reliable, low‑latency messaging across edge, cloud, and AI components. The platform’s unified architecture combines broker, rule processing, and data integration, reducing the need for separate middleware. Its open‑source Apache‑2.0 core and free tier make it accessible for experimentation, while the Business Source License governs the unified feature set.