I built a deterministic engine for I Ching (六爻 / Liu Yao) hexagram casting and open-sourced the core (Apache-2. 0). I want to be upfront that the interesting part here is not the divination — it's a testing problem, and I'd like feedback on how I handled it.
Source: [Hacker News](https://github.com/yaomancy/liuyao-engine)