on: we work at a startup that’s making an app
to generate custom exercise workout plans. The backend is written in Rust, and
the algorithm that generates the workout plan takes into account many factors,
such as the app user’s age, body mass index, exercise preferences, recent
workouts, and an intensity number they specify. The actual algorithm used isn’t
important in this example; what’s important is that this calculation takes a
few seconds. We want to call this algorithm only when we need to and 