Comment by smorrow

The most "research" thing I'm aware of 9front (since you're speaking in present tense) doing is that GEFS needed to work out a lot of things for itself that weren't in the Bε-tree proof-of-concept FS that came before.

I dunno how "close to the metal" you'd consider that.

("GEFS" being a disk filesystem that's been discussed on HN.)