Hi All, Okay, so, I've started working jml's "really disconnecting" blog post into a more generic set of tooling for testing protocols talking to each other over real networking like this: https://github.com/cjw296/carly/blob/master/tests/test_line_receiver_server.... Very interested in peoples thoughts, and especially if you can spot any bugs in these two: https://github.com/cjw296/carly/blob/master/carly/hook.py https://github.com/cjw296/carly/blob/master/carly/context.py Thanks for all the help so far, it's certainly helping me get my head around this all :-) Chris PS: Real networking is bad, yes, I know: slow, unreliable, etc ;-) However, in most of the testing I do, I end up having to hit a real database server to check my code works with it, so a few more tcp connections to localhost is not the end of the world!