@jmikola hey Jeremy, I can't seem to be able to use |= to combine the bit flags using the mongoc_query_flags_t type, as it would give an error that says invalid conversion from 'int' to 'mongoc_query_flags_t' if I uncomment this line. However, the query_collection function in mongoc-tail.c (https://github.com/mongodb/mongo-c-driver/blob/ef6622424fd0eb91bbde0ea9dba35fc83a380b9d/examples/mongoc-tail.c#L37) uses this approach and they are able to test it (https://github.com/mongodb/mongo-c-driver/blob/ef6622424fd0eb91bbde0ea9dba35fc83a380b9d/tests/test-secondary.c#L60). Is there any possible reason why it doesn't work in this case?