Utility to simulate simple http responses

I'm doing qui开发者_StackOverflow中文版te a lot of work with a javascript messaging system at the moment and end up making lots of use of netcat scripts to monitor and simulate as yet unimplemented server responses.

Does anyone know of a utility that can easily manage this sort of thing for prototyping purposes other than setting up a full webserver?

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Check Node.JS (depends on V8).