mqtt-broker

A production-grade MQTT 3.1.1 broker implementation in Rust.

Features

• 🚀 High Performance — Async I/O with Tokio, handles 10,000+ concurrent connections
• 📡 Full MQTT 3.1.1 — All 14 packet types with complete protocol compliance
• 🎯 QoS 0/1/2 — Complete delivery guarantees with proper state machines
• 🌳 Topic Wildcards — O(k) trie-based matching for + and # wildcards
• 💾 Retained Messages — Automatic delivery to new subscribers
• 🔄 Session Persistence — Clean and persistent session support
• ⏱️ Keep-Alive — Automatic connection timeout detection
• 🛡️ Production Ready — Comprehensive test suite with 176+ tests

What is MQTT?

MQTT (Message Queuing Telemetry Transport) is a lightweight publish-subscribe messaging protocol designed for constrained devices and low-bandwidth, high-latency networks. It’s widely used in:

• IoT (Internet of Things) — Sensor data collection, device control
• Home Automation — Smart home devices, lighting, thermostats
• Mobile Applications — Push notifications, real-time messaging
• Industrial Systems — SCADA, telemetry, monitoring

Quick Example

# Terminal 1: Start the broker
mqtt-broker

# Terminal 2: Subscribe to temperature readings
mqtt-consumer "sensors/+/temperature"

# Terminal 3: Publish a temperature reading
mqtt-producer "sensors/living-room/temperature" "23.5°C"

Next Steps

• Installation — Get mqtt-broker running
• Quick Start — Your first pub/sub in 5 minutes
• MQTT Concepts — Learn the protocol basics