I guess that depends on what you mean by type of "extension point". To me second level caching is a "type of extension point", so clearly that does not fit your mental model. What I think you are asking is whether you need to implement Integrator (and I assume you mean in the 5.0 code) for each place that extension points can get registered. If so, no, thats not what I was saying. Today there is an Integrator contract. It is what it is and does what it does. That won't change. In fact, what you ask (if I am right) is really the point of Contributors.

What I was saying is that, if I had a do-over I'd rename that Integrator contract to SessionFactoryServiceRegistryContributor and (re-)introduce Integrator as described in my comment above.

To avoid confusion here (I can feel it lets call this new unified, correct Integrator contract Integration. The idea was that OGM, for example, would supply just one Integration, which would in turn supply all the "contributions" on OGM's behalf. I think it might help you understand if you took a look at the existing contribution contracts. I listed some in passing in my initial comment, some of which exist already some of which do not. The ones that exist exist only on the ORM metamodel (5.0) branch. < /a>

Hopefully this clarifies...