Really fun idea and a great implementation. I have been trying to come up with programming puzzles for my own project https://www.dev-esc.com - an escape room for devs

My own “Show HN” is at https://news.ycombinator.com/item?id=28579191

andersource would you be willing to consider letting me incorporate something like a checkerboard puzzle?

Have you any metrics on average completion times etc? Striking the right balance between fun vs difficult has proved tricky for me.