Pollen, written in Racket, is arguably a "dsl for specifying ssgs"
My daydream is to make a _good_ technical documentation system with it that is usable by the everyman, but it's still just a bit too much of a stretch. Markdown + pandoc + LaTeX templates get close, but LaTeX templating is a nightmare, and markdown is far too limiting and lacks expressivity (without ad-hoc DSL's slapped on top).
If anyone has a good pollen tutorial or example repo, I'd _love_ to know of it.