I implemented the rules of Ora et Labora. Every card's ability is some fun puzzle of enumerating all the legal ways to play it. Some are simple like "go here and you get an amount of sheep", others are "you can convert an amount peat to coal here" so if you have 5 coal, you can offer 0, 1, 2, 3, 4, or 5 peat as input. The more fun problems are like "convert 3 different resources into 6 of any one type of basic resource" or "convert four to bread for 0.5 energy each" and wood is worth 1 energy, peat 2, and coal 3 energy. Lots of fun combinatorics.
It's all open source and playable at https://ora.kennerspiel.com