Best Free Message-Oriented Middleware

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.

HiveMQ is the most trusted enterprise MQTT platform, purpose-built to connect anything via MQTT, communicate reliably, and control IoT data. The platform can be deployed anywhere, on-premise or in the cloud, giving developers the flexibility and freedom they need to evolve as their IoT deployment grows. HiveMQ is reliable under real-world stress, scales without limits, and provides enterprise-grade security to meet the needs of organizations at any stage of digital transformation. The extensible platform provides seamless connectivity to the leading data streaming, databases, and data analytics platforms, plus offers a custom SDK for a perfect fit in any stack.

With Azure SignalR Service, adding real-time communications to your web application is as simple as provisioning a service—no need to be a real-time communications guru! You don't have to provision and maintain servers just because you need real-time features in your solution. SignalR Service is fully managed which makes it easy to add real-time communication functionality to your application. No more worrying about hosting, scalability, or load balancing – it's all handled automatically. Benefit from everything Azure has to offer! Easily integrate with services such as Azure Functions, Azure App Service, Azure Active Directory, Azure Storage, Azure Analytics, Power BI, IoT, Cognitive Services, Machine Learning, and more. Use the SignalR Service Premium Tier to leverage enterprise capabilities such as auto-scaling, higher SLA, Azure Availability Zone support, and rate limiting. Send advanced metrics to Azure Monitor or integrate with other monitoring solutions.

StreamNative redefines streaming infrastructure by seamlessly integrating Kafka, MQ, and other protocols into a single, unified platform, providing unparalleled flexibility and efficiency for modern data processing needs. StreamNative offers a unified solution that adapts to the diverse requirements of streaming and messaging in a microservices-driven environment. By providing a comprehensive and intelligent approach to messaging and streaming, StreamNative empowers organizations to navigate the complexities and scalability of the modern data ecosystem with efficiency and agility. Apache Pulsar’s unique architecture decouples the message serving layer from the message storage layer to deliver a mature cloud-native data-streaming platform. Scalable and elastic to adapt to rapidly changing event traffic and business needs. Scale-up to millions of topics with architecture that decouples computing and storage.

Responsive applications keep users engaged and developers inspired. Rise to meet these ever-increasing expectations with the DataStax Astra Streaming service platform. DataStax Astra Streaming is a cloud-native messaging and event streaming platform powered by Apache Pulsar. Astra Streaming allows you to build streaming applications on top of an elastically scalable, multi-cloud messaging and event streaming platform. Astra Streaming is powered by Apache Pulsar, the next-generation event streaming platform which provides a unified solution for streaming, queuing, pub/sub, and stream processing. Astra Streaming is a natural complement to Astra DB. Using Astra Streaming, existing Astra DB users can easily build real-time data pipelines into and out of their Astra DB instances. With Astra Streaming, avoid vendor lock-in and deploy on any of the major public clouds (AWS, GCP, Azure) compatible with open-source Apache Pulsar.

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.