I found some hours and once I got started, implementing the Enhancer was pretty much straight forward: https://github.com/raphw/hibernate-orm

I have not yet run any tests but it looks good for the moment. Similar to the Javassist implementation, I had to write some byte code manually using the underlying ASM API. I do however claim that this is still better readable than what we had before. Other than that, it looks good to me.

I will still need some time to test the implementation before I would start cleaning up when I could prepare a PR.

All changes to the Enhancer / EnhancementContext API are also implemented as we discussed. I will also join HipChat, sorry for the delay, too much work these days.