This is definitely unfortunate, but in my defense I was not aware of Rust's mio (or anything related to Rust beyond its existence) at the time of writing and naming my library. I have no emotional investment in the name, so I'm open to suggestions should anyone take issue with it.

I also think Rust's mio is sufficiently behind-the-scenes that the only people who will encounter it will already be well aware of its purpose; typical Rust users will be two levels removed from mio, if they're using it at all. Namespace collisions matter more for end-user software than foundational libraries. :)