Sounds like this meets the requirements: https://github.com/niklasf/python-chess https://github.com/niklasf/python-chess > very carefully respects all possibl

Sounds like this meets the requirements: https://github.com/niklasf/python-chess https://github.com/niklasf/python-chess > very carefully respects all possible game-ending pathways Not sure exactly what this one means but it implements a is-game-over method, so you could do MCTS with it. > a translation of a chess board into an array that a NN could understand Chess positions are represented by sets of 64-bit integers so I don’t think this would be a blocker. > and a schema by which to flatten the array of all possible moves (both legal and illegal) into a single vector The list of legal moves is a set of bitboards as well.