I actually think this is quite neat, but I am a bit worried about caching.

Someone mentioned rails, and rails have a lot of facilities to set correct cache headers for assets (css, js, images etc) and for dynamic content (for logged user in and/or for pages that are dynamic but public).

If you're deploying static files via a vanilla web server, you also get a lot of that for free, via the file meta-data.

I would expect a framework for publishing sites to showcase a minimum of good caching (client cache, ability to interact with a caching reverse proxy like varnish - and/or a cdn).

I get that after reading your blog post, so that's fair. Maybe it's just a case of the magic trick that's missing that third act.

Clicking around with the Dev Console open and watching the pages in Sources was enjoyable.