Morphium 6.2.6 is out — and it repairs something that should never have been broken in the first place: replicaset failover. A chain of bugs (chief among them a timeout that silently multiplied itself by 100) meant the driver practically never recovered after the primary died: writes hung, messaging stayed dead. After the fixes: full write throughput ~25 seconds after a kill -9, no lost messages. Also on board: a fix for `findOneAndUpdate` deleting documents instead of updating them on read-cache hits, a self-deadlock in the SingleMongoConnectDriver, and `$setOnInsert`/upsert support in the InMemoryDriver.