[inertiatic]

>I'm still looking for a systematic approach to make a hybrid search (combined full-text with embedding vectors).

Start off with ES or Vespa, probably. ES is not hard at all to get started with, IMO.

Try RRF - see how far that gets you for your use case. If it's not where you want to be, time to get thinking about what you're trying to do. Maybe a score multiplication gets you where you want to be - you can do it in Vespa I think, but you have to hack around the inability to express exactly that in ES.