This is a schematic of my DIY RGB strip project. Everyone with little programming knowledge can reproduce it.
Details of functionality
The NodeMCU tries to load the configuration from a file on SPIFFS. If fails then starts a captive portal as a WiFI AP and waiting for connection for 3 minutes.
The user enters the home's AP data, the MQTT username and password and the Domoticz MQTT topic names. Then the device is restarting itself in WiFI station mode and waiting for MQTT messages.
If a specified MQTT message has been arrived and processeed successfully, the device adjusts the PWM outputs and the LED strip's RGB values according to the message's payload.
See the GitHub page here: https://github.com/dzooli/nodemcu-rgbstrip