What it is

OpenMQTTGateway is an open-source C++ gateway firmware for ESP8266 and ESP32 boards that connects local radio and sensor protocols to MQTT. It lives in the home-automation ecosystem and is associated with Home Assistant, OpenHAB, NodeRed, and AWS-IOT. The project aims to unify various technologies and protocols into a single firmware, reducing the need for multiple physical bridges.

The concrete problem it solves is fragmentation in small IoT setups. A user may have 433 MHz, 315 MHz, or 868 MHz radio devices, infrared transmitters and receivers, Bluetooth Low Energy sensors, beacons, plant sensors, scales, tire-pressure sensors, barbecue thermometers, or LoRa devices. Each may require its own hardware adapter or bridge. OpenMQTTGateway brings those inputs and outputs into MQTT topics, which makes them easier to route, display, or automate through compatible controllers and services.

Key capabilities

• It runs on ESP8266 or ESP32 hardware, with Arduino and Arduino Uno also referenced.
• It supports bidirectional 433 MHz, 315 MHz, and 868 MHz radio communication, so it can receive and transmit RF signals.
• It includes infrared communications, allowing IR devices to be handled through the gateway.
• It supports BLE and Bluetooth, including beacon detection and device families such as mi flora, mi jia, LYWSD02, LYWSD03MMC, Mi Scale, TPMS, and BBQ thermometer compatibility.
• It supports LoRa, extending the gateway to another long-range radio technology.
• It uses MQTT as the common protocol, and can be used with Home Assistant, OpenHAB, NodeRed, and AWS-IOT.

Who uses it and how

• Home-automation users flash an ESP8266 or ESP32 board and use it as a single bridge for mixed radio, IR, BLE, and LoRa devices.
• Sensor collectors use it to expose supported BLE sensors, thermometers, scales, plant sensors, beacons, tire-pressure sensors, and barbecue thermometers over MQTT.
• RF and IR users use it to connect RF and IR devices to MQTT through the gateway.
• Platform builders use it with Home Assistant, OpenHAB, NodeRed, or AWS-IOT to create dashboards, automations, or cloud-connected flows from local device data.

Getting started

The README points to a browser-based upload page for flashing a board without additional software, and to PlatformIO for building a custom configuration. The documentation also references a Getting Started guide and a reference sheet with functions and pinouts.

When to use it — and when not to

OpenMQTTGateway is a good fit for users who want one open-source firmware for ESP8266 or ESP32 hardware and are comfortable choosing boards, flashing firmware, and mapping MQTT topics. It is less suitable for users who want a ready-made product rather than firmware they configure themselves, because the README lists Theengs Bridge and Theengs Gateway as related products. The project has 48 open issues, so users should expect ongoing configuration and compatibility work.