[irrelative]

As a home coffee roaster myself (including building my own roaster) I'm guessing that experimenting programatically with roast times would cause the smoke alarm to go off regularly.

I guess you could hope that later generations get better at this, but there's always the risk of a 5 alarm mutation ;-)

[bioweek]

Hook up a smoke detector to turn off the roaster. If smoke doesn't clear in 1 minute, have it shoot off a fire extinguisher. Problem solved.