However, JCache has some flaws so having a native connector is something to investigate.

If need be I can hop on a hangout & discuss this. While I wrote the initial adapter and do seem to remember some caveats, iirc nothing seemed blocking and/or a huge problem. But I may well be misremembering. Also I may have let some stuff suboptimal (may have been fixed since). iirc I mainly did this to test the 107's proposal back then. Some thought it couldn't be done entirely. Anyways… I need some background again, but hopefully my brain remembers. And that'd need mapping to the new SPI to see how it applies today (still?)… Chris Dennis, you might be best suited if you can find 30 minutes or so. Might be useful, if only to document what these are. Maybe infinispan people may be interested?