The implementation should take into account the following functionality:

• transactions (see https://github.com/mongodb/specifications/blob/master/source/transactions/transactions.md#what-commands-can-be-run-in-a-transaction)
• retries (see https://github.com/mongodb/specifications/blob/master/source/retryable-writes/retryable-writes.md#supported-write-operations)
• CSOT

The implementation will encode ops and nsInfo parts of the bulkWrite command as part of the first and (for now) only section of the OP_MSG wire protocol message with payload type 0, and will not implement any splitting of ops and nsInfo, as well as splitting of the bulkWrite command if the number of write models is too large.

Unified spec tests are to be implemented together with the API implementation because they will give us some confidence in the implementation.