5.5.5.Final was released today.
It’s our most recent stable version, with only minimal changes to address issues identified in the previous release.
This is also our "lightest" release ever, in terms of memory consumption. But this is the result of many years of work, not any specific change in this particular build, so I’ll follow up with a dedicated analysis as we collect more data.
For the full changelog see the Release Notes.
All details are available and up to date on the dedicated page on hibernate.org.