Implementing Ishido, a game from the 90s, using the Racket graphical facilities (alex-hhh.github.io)

This is a great post. Pasteboards and snips are so powerful.

I couldn't care less.

It seems like you could play this game using a Qwirkle set. The rules are very similar, but Qwirkle looks at the entire run a tile is involved in, not just the 4 immediately adjacent pieces. And the board is unbounded in Qwirkle. (Other minor differences, too)