We are working with Alex,creator of µWebSockets (https://github.com/uWebSockets/uWebSockets) on moving all connectivity and networking aspects to low level C

yes, that's one major aspect of it. engine.io adds is own protocol and isn't exactly the most performance tuned library

Is there some data available on which factor the perfomance benefitted from this change (like some benchmark results)?

Sorry, it doesn't let me reply for some reason :-( Development is in progress, there will be figures soon

It seems like you have to wait some seconds for the server to process the comment, if you refresh it should let you comment again. Anyway, looking forward to the data release, through a blog post I suppose?

That feature of HN is by design. It's there to force you to think about your replies instead of engage in knee-jerk flamewars. :)

Would this mean you are getting rid of engine.io as the base, or is this just meant to be a general addition?