Recently, I made a chess program in Python and published the source on github here. The code is just under 1000 lines, about 20% of which is dedicated to the AI. In this post I’ll cover how the AI works, what each part does. and why it works like that. You can just read through, or download the code and mess around with it as you read. The AI is all in the AI.py file, although it might help to look at the other files to see what the classes that the AI depend on do.