I am a kernel hacker, and I have worked with io_uring, and I can safely judge that it is very good -- but the main issue is that it represents a totally differe

I am a kernel hacker, and I have worked with io_uring, and I can safely judge that it is very good -- but the main issue is that it represents a totally different approach to I/O (and syscalls generally, which are just I/O in other words), which is going to take the ecosystem a while to reform around. Note that the sample code in the OP's article is much more complex than the traditional approach. It's also very Linux-specific, so any software which takes advantage of it will be less portable or will have to write multiple I/O backends. It's also nontrivial to understand and use effectively, so adding good io_uring support to a project is an effort.