The Growler vhost server acts as forwarding agent for HTTP requests to multiple domains hosted from a single server. This is an implementation of the service using the Growler microframework to handle the incoming request. As with everything Growler, all events are asynchronous, and handled when-needed.
This package comes as a binary, which can be run in the form of growler-vhost -c <config_file>, specifying the path to the config file to use as parameters.
I have a hope that optimizations can be made such that forwarding the request to another growler server takes (almost) no extra resources. As the request can easily be parsed once into the format that the growler application already uses. We are a long way from that, though.