Jepsen: MongoDB 3.4.0-rc3
This fall, I worked with MongoDB to design a new Jepsen test for MongoDB. We discovered design flaws in the v0 replication protocol, plus implementation bugs in the v1 protocol, both of which allowed for the loss of majority-committed updates. While the v0 protocol remains broken, patches for v1 are available in MongoDB 3.2.12 and 3.4.0, and now pass the expanded Jepsen test suite.
You can read the full analysis at jepsen.io.