The new write methods from the CRUD spec should be backported to 2.9. They should be implemented as wrappers around the existing methods, which will not be hard deprecated. The methods we need are:

• insert_one (wrap existing insert method)
• insert_many (see the 3.x branch for implementation details)
• update_one (wrap existing update method)
• update_many (wrap existing update method)
• delete_one (wrap existing remove method)
• delete_many (wrap existing remove method)
• replace_one (wrap existing update method)
• find_one_and_delete (wrap existing find_and_modify method)
• find_one_and_replace (wrap existing find_and_modify method)
• find_one_and_update (wrap existing find_and_modify method)
• bulk_write (see the 3.x branch for implementation details)

Note that the results module will also have to be backported, since the new insert, update, replace, and delete methods all return a specific result class. Most of the operations module will also need to be backported.