The best alternative, by far, is don't require async. Async is much harder to work with than other methods of gaining concurrency, and its benefits (like not ne

The best alternative, by far, is don't require async. Async is much harder to work with than other methods of gaining concurrency, and its benefits (like not needing OS context switches) are irrelevant to most developers. There is no good reason that the majority of Rust libraries force their users into async in all its messiness.