Many thanks, that's useful to know. I'll look at why it attempts to enhance more than what's needed.

And sure, it should be safe to use Javassist. In fact as you noticed Javassist was the default, and the integration point didn't change much yet: the move to Byte Buddy is driven by future needs related to Jigsaw modules.

To switch the enhancer implementation it I'm afraid there is no plugin configuration option, as we expect to remove the Javassist option in the near future (which is why your feedback is great to have now).

You should be able to configure the hibernate.bytecode.provider option via either environment variables or JVM properties; these would need to be set before the Maven plugin is run.