[zemo]

yes, using a channel's buffer for resource management like this is a common pattern. I can't say that I necessarily like this pattern, but... yes, it is common.

In this case, this particular part of the application is worth questioning, because the error condition isn't reasonable. Right now, if the proxy is full, it accepts a TCP connection from a client, and then it just ... stalls. It doesn't disconnect the client, it doesn't read from the client, it just hangs. So if a client were to actually connect to this proxy when it's full, they'd just open up a connection and wait.

Using sync/atomic package isn't common. Yes, you could do it, but it would be more common to just have a goroutine with a counter in it, and a select statement to serialize increment and decrement messages.

And then there are the actual handlers, which throw away the error information if there's an error actually writing to the connection.