Compartmental models in Rust

I've been learning a bit of Rust in the past few weeks, mostly by writing some basic SIR-type models (both as ODE systems, and as continuous-time and discrete-time Markov chains). It takes most (maybe all) of the things that I like about OCaml and adds more great features and safety guarantees, thanks to its ownership model and lifetimes. It's also very fast (no garbage collector, zero-cost abstractions) and has fantastic tooling, although compilation times can be very long, and package ("crate") availability can be very hit-or-miss. I've enjoyed it enough that I'm looking forward to writing more Rust code in the future. Although I've no plans to rewrite pypfilt or epifx in Rust any time soon!