Investigate changing cachy output

<img width="1227" height="737" alt="Image" src="https://github.com/user-attachments/assets/8f1f608f-11e8-4637-ab6a-2ebede8b6d9c" />

CI passes but running the individual notebook creates a different output, might be unwanted side effects of running notebooks in parallel. Maybe use different seeds in each notebook and check if calls to `random` can be in unpredictable order.