eventual

Curious if someone has tried this and Eventual[0] with any thoughts on how they compare. https://github.com/carllerche/eventual

You're right, that site should be updated with those as other parts of the ecosystem that aren't yet mature. There's work on non-blocking IO at https://github.com/carllerche/mio, which is looking like one of the more promising approaches, as well as https://github.com/carllerche/eventual which provides higher-level abstractions over it. There has been some discussion of adding some language support for something like async/await/yield from other languages, but nothing concrete in the near future on the language front. So, there's usable third-party libraries for it (at least, if you're on a Unix like platform), language support is in the realm of "it would be nice someday".

Rust has definitely been a pleasure to work with. I have been experimenting with a Future & Stream [1] abstraction in Rust that would allow easily describing complex concurrent and async operations and to allow easy composition, not unlike ES 6 promises. The interesting thing is that, thanks to Rust's ownership system, it is easy to discover when handles to a future value go out of scope. This allows the library to reuse internal resources to make the overhead of using the library as light as possible. For example, a Stream is modeled as a sequence of futures (more specifically a future of the next value and a new stream representing the rest of the values, kind of like lazy-seq in clojure but async), but instead of allocating one future for each iteration of the stream, the same internal structure is reused while still being able to expo