Scott Marlow The reason I ask is that changing just the Hikari version as requested leads to problems running even the verrrrry simple test in hibernate-hikari. Its one of those strange cases though where I get the failure from the command line, but cannot reproduce from within IDE to debug it.

This is is slated for 5.1 which is the next major version, so I am ok with updating some dependency versions. I just don't want to end up running into the same issues we invariably seem to run into when upgrading Javassist. In fact I wonder if we should consider (moving forward) doing a shadow/shade of Javassist for Hibernate's use.

For the short term, I'll try updating Hikari (to 2.3.9) + Javassist (to both 3.18.2-GA and 3.20.0-GA) and see how that works.