Not exactly related to Go/PyPy, but I'm curious whether you can say something about how you handle memory and bandwidth constraints?

E.g. what do you do if you want to send notifications to lots of clients but for some the connection is very slow (you would probably need to buffer the data)? Do you have hard limits of maximum buffered data until you close the connection? End to end backpressure (for which channels are quite good) doesn't seem like the best option for 1:N broadcasts, because then the slowest receiver slows down all others.

And what do you do with connections which are sending you lots of (probably unexcepted) data? Stop reading from that socket?