Huge fan of your work! I was curious if you've ever attempted to run your (or part of) Mongo test suite against FoundationDB using their DocumentLayer since it's supposed to be Mongo API compatible.
IIRC one of the FoundationDB engineers tested with Jepsen and found that it passed in its default configuration, but the blog post seems to have disappeared.
Thanks for firing up the time machine! I've been using FDB for a little over a year now and can't recommend it enough. Such a solid piece of meticulous engineering.