NATS

NATS is a simple, secure, and high-performance open-source messaging system designed as the connective tissue for cloud-native applications, IoT messaging, and microservices architectures. Originally created by Derek Collison (formerly chief architect at TIBCO and Google) in 2010, NATS is now maintained by Synadia Communications and the Cloud Native Computing Foundation (CNCF). The server is written in Go as a single binary with no external dependencies, capable of processing millions of messages per second with microsecond latency. NATS supports four core communication patterns: publish-subscribe (at-most-once delivery with fan-in/fan-out), request-reply (synchronous or asynchronous), JetStream persistence (at-least-once or exactly-once delivery with durable streams, work queues, key-value stores, and object storage), and subject-based messaging with wildcards. Additional features include: zero-trust security with TLS, JWT-based decentralized authentication and authorization, leaf nodes for edge connectivity, super-cluster topology with route auto-discovery, MQTT protocol support, WebSocket support, and message payload encryption. Client libraries are available for Go, Java, Python, JavaScript, TypeScript, C, C#, Rust, Ruby, Swift, Dart, Elixir, and Haskell. As of 2026, NATS has over 15,800 stars.