The best part is probably that this system is so simple that it allows for many extensions, customizations or new rules and variations. You could solve this on

The best part is probably that this system is so simple that it allows for many extensions, customizations or new rules and variations. You could solve this on prolog, for example, defining tiles as 4 numbers (one for each side), and what you effectively get is a distribution of tiles, that you can later "paint" as you want. You could later add even softer constraints, like density or others.