@TerryHancock RSS can be a static file, and for a SSG it would make the most sense for it to be a static file.
There are no dynamic aspects, and it is already federated, in the sense the WWW is.
You could imagine (and I have created) a centralized site that mixes together other people's RSS feeds into one combined html/RSS feed. But that is not federation, it is an RSS client web app.