Show HN: Emergence: a fun little app to play with chaos

I built this to demo some cool simple concepts in emergent behaviour and to showcase my services for science/engineering app building.

There are 21 simulations: cellular automata, flocking, a traffic model, an Ising magnet, lattice Boltzmann fluid flow, fractals, a few chaotic systems. It is plain TypeScript with no framework and no runtime dependencies, and everything runs client-side.

A few things I'd point at:

- Each simulation is a plug-in. The model is a set of pure functions; the app only knows a small interface (step, draw, controls, stats, docs). - The explanations beside each one make claims, and where the model can check a claim there is a test that does. That caught my own documentation being wrong more than once. - The fluid solver does about twenty million cell updates a second on one core. Doubling the grid would cost eight times as much, so it is 300x120 with smoothed drawing.

Write-up: https://modlit.io/writing/emergence/

Happy to answer questions about any of the models or how it is put together.