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workshop: Build your own IoT cloud with MQTT
Using a Raspberry Pi and some ESP8266 devices for your IoT cloud
Using MQTT to connect and use IoT devices
Use a MQTT broker, some daemons and other tools on a Raspberry Pi to connect and use the data from/to ESP8266 devices.
The ESP8266 devices (Wemos D1 mini/NodeMCU) will be programmed with and Arduino environment. So knowledge about the Arduino environment is essential to work with the ESP devices.