Many users here do use a microcontroller unit, commonly abbreviated MCU (the esp8266 is one of the microcontrollers that people use). They purchase the microcontroller (typically $3-$10) and any sensors, relays, or switches that they would like to integrate with the microcontroller. At this point they write or modify an arduino sketch to program the microcontrollers to do what they want it to do in regards to the sensors, relays, or switches. This can then be integrated with hubitat with this: [Release] HubDuino v1.1.7 - Hubitat to Arduino / ESP8266 / ESP32 / ThingShield Integration (ST_Anything)
This may sound complicated and to a certain extent it is. But I have just started playing around with it and have built and integrated some really cool stuff and I have no prior experience in coding or computer programming.
