Where it really breaks down is that there's no spawn without tying the library to e.g. tokio. Also, the other way around might be simpler. If the library wants

Where it really breaks down is that there's no spawn without tying the library to e.g. tokio. Also, the other way around might be simpler. If the library wants to be async, make it async-only, and let callers block_on it. https://docs.rs/tokio/latest/tokio/runtime/struct.Runtime.html#method.block_on https://docs.rs/tokio/latest/tokio/runtime/struct.Runtime.ht...