A socket, pipe, or shared memory region?

A network connection to localhost?

Running the backend as a child process of the frontend, and using standard io?

Zigbee or Zwave temperature/humidity sensors are common. Add a 3-circuit relay box and you can simulate the behavior of pretty much any thermostat with a few rules.

HA or any other system that can toggle outputs based on sensor thresholds would work just fine.

there are some subtleties with real HVAC thermostats, like running your AC compressor at least five minutes and ensuring that it stays off for at least 5 minutes when it’s turned off.

Never good to intentionally pollute.

Is COBOL subject to buffer overflows and use-after-free bugs? I honestly don’t know.

I don’t recall the COBOL code I’ve read using pointers.