Code using a fixed timestep usually explicitly takes advantage of this design, and is intentionally a hand-rolled state machine, so async doesn't improve it IMH

Code using a fixed timestep usually explicitly takes advantage of this design, and is intentionally a hand-rolled state machine, so async doesn't improve it IMHO. Async is meant to hide the event loop (the ticks). It depends how deep you want the ticks integrated with your async code. At minimum you can do: async { loop { next_tick_time().await; do_tick(); } } You could also write your own async executor that just polls all spawned futures on every tick, instead of the event (waker) mechanism used by async. But both approaches are IMHO pointless. Async is meant to be a sugar on top of events and run code only when the events happen, not run it all the time at a fixed timestep.