“Don’t tell anyone, but I already have plans for a better version of Sockfish that will be much harder to detect!”
A Raspberry Pi Zero in a pocket, vibration motors in the shoes and Stockfish doing the thinking. He lost the first game because the voice input heard g6 instead of g2. He still beat a stronger player in the second. One hobbyist built this in his spare time, so assume over-the-board chess is not as clean as anyone claims.