I've always enjoyed lichess's chess API: https://github.com/lichess-org/scalachess/tree/master/src/main/scala https://github.com/lichess-org/scalachess/tree/mas

I've always enjoyed lichess's chess API: https://github.com/lichess-org/scalachess/tree/master/src/main/scala https://github.com/lichess-org/scalachess/tree/master/src/ma... It's funny because I remember comparing it to mine that I had tried to write during college, and appreciating how much better it is. Pay attention to how there's a bunch of different types of chess in there too, and how that's factored.