In honor of my espresso machine being fully plumbed in (water supply and drain line!) it’s time for another coffee hack. When I wrote my basic coffee roaster how-to, I seriously thought that I’d never see anyone do this, but  installed a programmable PID controller on his popper coffee roaster setup. This particular PID can be programmed to ramp the temperature over time to create an actual roasting profile, rather than manually adjusting the set points. The original page was here, but I had to pull it out of the internet archive.