One of my coffee friends is none other than Koffee Kosmo. Majority of people in the coffee world know him as the person that invented the KKTO or Koffee Kosmo Coffee Roaster.
The KKTO can be bought as a kit or KK is kind enough to share his design so anyone can make one at home.
I have to add that before everyone goes off and orders the kits, they are not available to buy in kit form due to a lack of availability of some important parts.
That doesn’t mean you can’t have a go at the DIY version, there are many many DIY versions in use around the world.