Best Free Message-Oriented Middleware

HiveMQ empowers businesses to unlock the full potential of their data with the most trusted edge-to-cloud IoT data streaming platform. Built on MQTT’s publish/subscribe architecture for seamless and flexible integration across operational technology (OT) assets and information technology (IT) applications, HiveMQ ensures businesses can efficiently connect, stream, and govern their data in real-time. With a focus on reliability, scalability, and security, HiveMQ helps organizations get their data AI-ready—enabling advanced analytics, predictive maintenance, and digital transformation. Leading brands like Audi, BMW, Liberty Global, Mercedes-Benz, Siemens, and Eli Lilly trust HiveMQ to modernize their operations, accelerate innovation, and create smarter, data-driven experiences. Visit hivemq.com to learn more.

Ably is the definitive realtime experience platform. We power more WebSocket connections than any other pub/sub platform, serving over a billion devices monthly. Businesses like HubSpot, NASCAR and Webflow trust us to power their critical applications - reliably, securely and at serious scale. Ably’s products place composable realtime in the hands of developers. Simple APIs and SDKs for every tech stack, enable the creation of a host of live experiences - including chat, collaboration, notifications, broadcast and fan engagement. All powered by our scalable infrastructure.

Middleware Observability & Management Software for Messaging, Event Processing, and Streaming Across Hybrid Cloud (MESH). - Complete observability and monitoring of Integration MESH with 360° Situational Awareness® - Securely manage, and automate configuration, administration, and deployment - Track, trace, and analyze transactions, messages and flows - Collect, monitor, and benchmark MESH performance meshIQ delivers granular access controls to manage configurations across the MESH to reduce downtime and quick recovery from outages. Provides the ability to find, browse, track, and trace messages to detect bottlenecks and speeding up root-cause analysis. Unlocks the integration blackbox to deliver visibility across the MESH infrastructure to visualize, analyze, report, and predict. Delivers the ability to trigger automated actions based on pre-defined criteria or intelligent actions determined by AI/ML.

CoreDX DDS is an easy-to-use, cross-platform, cross-language Inter-Process Communication (IPC) library. CoreDX DDS is high-performance and low-overhead, with low latency to support real-time control and high message throughput to support high bandwidth data. CoreDX DDS provides secure, robust, flexible, and dynamic data communications. Based on open standards for guaranteed Interoperability and long-term viability, CoreDX DDS is the preferred IPC for a wide variety of distributed software programs, from mobile games and consumer electronic devices to surgical equipment, health care applications, complex DoD systems, and robots working in space. Programmers like CoreDX DDS because it is easy to use and provides many features difficult to implement by hand, and not found in other IPC libraries. With features like integrated end-to-end security, data filtering and storage, data presentation, and event notification options, CoreDX DDS allows programmers to focus on their applications.