[herbst]

It reads like it uses a lot of buzzwords for simple concepts, which makes it hard to understand.

From my understanding it's some kind of web framework that mixes frontend and backend. But I have no concept what code hydration is, shared states, reactive web elements, and so on. I never been into React and stuff, but Fullstack is what I do.

Shared states sounds like it has some kind of database, hydration surely is some kind of layout rendering, reactive components could be smart DOM event handling... But that's just assumptions.