This is a similar challenge to e.g. C++. Can it be done with SFINAE? Yeah, probably. Does Servant need pseudo-dependent types and does Wren need lenses? Maybe

This is a similar challenge to e.g. C++. Can it be done with SFINAE? Yeah, probably. Does Servant need pseudo-dependent types and does Wren need lenses? Maybe we could both make and respond to an HTTP request without getting into some pretty heavy shit?