Currently, you can only play against yourself, and check, checkmate, en-passant and castling isn’t implemented yet, but everything else should shork exactly as you expect!
I played around with it for a few minutes and at one point, playing against the bot, it froze on its turn, when it had plenty of legal move options.
Another thing I noticed is that you’re allowed to play illegal moves, such as putting your own King in check. I haven’t fully explored other possible illegal moves but you’ll also need to ensure you’re careful about implementing castling as that can be a little thorny with illegal moves like castling through check etc.
If you need any advice or want me to test anything for you, let me know! I’ve never attempted to code a chess app but props to you for taking on the challenge. I’m a decent enough chess player though, so can offer help with that side of things if needed.
At some point, you might also want to include options for resignation, or forced draw by repetition, as there are certain cases where it’s impossible for either side to win and so you’ll get stuck otherwise. This also includes stalemates of course too.
Oh, that’s interesting! Is that because they are both filling in cells according to a criteria? You replaced the game of life rules with the Mandelbrot set equation to fill in the cells?
I think you might enjoy this book, A New Kind of Science by Stephan Wolfram, have you heard of it?