I've got a few Unos and Megas dotted around the house driving 1-wire temperature sensors, and 8 relay boards controlling heating, lighting and appliances. These are driven from Homeseer.
The Arduino plugin for Homeseer lets you configure each pin from within Homeseer, which means I don't have to go and update the sketch in the awkwardly located Arduinos every time I change something, and maintain copies of each sketch.
I'm moving across to Home Assistant, and starting to experiment with integrating everything with MQTT.
Has anyone created a sketch that will pull the pin configuration from an MQTT topic which could be stored and maintained in Home Assistant? Perhaps based on Arduino MAC address?