Yes, Oracolo is pure js rendering. I hate this, for many reasons, but it's the only way to pack the full blog in a single html file that everyone can easily deploy, anywhere. And this is the main goal. Oracolo target are not professional bloggers that need a ultra performant website.

Btw, Google indexes js, so things should improve over the time:

https://developers.google.com/search/docs/crawling-indexing/javascript/javascript-seo-basics

> open websockets to a bunch of relays which can be very slow

You choose your relays, exactly how you pick your hosting.

> I don't have experience with caching websocket, that might be a simple solution.

I planned something about it, but the difference in terms of actual user experience (not Google numbers) is not worth the trouble.

Maybe I will add structured data to improve accessibility, SEO and discoverability.