For me, once I wanted to scale asyncio within one process (scaling horizontally on top of that), only two things made sense: rust with tokio or node.js.

Doing async in python has the same fundamental design. You have an executer, a scheduler, and event-driven wakers on futures or promises. But you’re doing it in a fundamentally hand-cuffed environment.

You don’t get benefits like static compilation, real work-stealing, a large library ecosystem, or crazy performance boosts. Except in certain places in the stack.

Using fastapi with async is a game-changer. Writing a cli to download a bunch of stuff in parallel is great.

But if you want to use async to parse faster or make a parallel-friendly GUI, you are more than likely wasting your time using python. The benefits will be bottlenecked by other language design features. Still the GIL mostly.

I guess there is no reason you can’t make tokio in python with multiprocessing or subinterpreters, but to my knowledge that hasn’t been done.

Learning tokio was way more fun, too.