People's honor and integrity. :) There are anti-cheating counter-measures but they would be trivial to defeat for someone who knows a little bit about how compu

People's honor and integrity. :) There are anti-cheating counter-measures but they would be trivial to defeat for someone who knows a little bit about how computer chess works. For example, Lichess is a free chess site and all the source code is open, except for the anti-cheating heuristics. However, getting a computer to play realistically like a good eight-year old wouldn't be to easy. The computer-generated moves would stand out much more due to the skill differential than, say, if a grand master cheated using a chess engine.