The architecture being experimented with here is essentially to design ReSpec as 
a thin layer on top of a dynamic loader. Each piece of functionality becomes a
small and self-contained plugin. Some plugins can call upon others, so that for
instance the W3C plugin would be the only one one needs to load for a W3C document
and it would take responsibility for calling in the others (different groups could
have their own refined versions of this, naturally).

This is built with RequireJS and jQuery.

This approach also makes it possible to reuse ReSpec in non-W3C settings, as well
as to optimise its running time by excluding plugins one doesn't need.