Breaking Changes

Backwards compatibility with driver version 2.7.0–2.14.x

Starting from 2.15.0, feature detection is implemented through maxWireVersion instead of buildInfo. This should have no user-visible impact.

Driver version 2.14.0 and later only supports MongoDB 3.6+. It cannot connect to clusters running earlier versions of MongoDB. If you need to connect to an older cluster, please use driver version 2.13.x or earlier.

Starting in 2.11.0, BsonSerializer.Serialize will throw an InvalidOperationException when attempting to serialize an array at the root of a BSON document. Prior versions would allow this invalid operation. See and for more details.