Comment by 0x457

> And due to instability of a few features (async trait, return impl trait in trait, etc) there is not really a standard way to write executor independent async code (you can, some big crates do, but it's not necessarily trivial).

Uhm all of that is just sugar on top of stable feature. None of these features or lack off prevent portability.

Full portability isn't possible specifically due to how Waker works (i.e. is implementation specific). That allows async to work with different style of asyncs. Reason why io_uring is hard in rust is because of io_uring way of dealing with memory.