Jepsen Disputes MongoDB’s Data Consistency Claims

In an article, MongoDB claimed their database passed “the industry’s toughest data safety, correctness, and consistency Tests”. In response, Jepsen published an article stating that MongoDB 3.6.4 had in fact failed their tests; the newer MongoDB 4.2.6 has more problems including “retrocausal transactions” where a transaction reverses order so that a read can see the result of a future write.