The core goals of Congo is to create a robust easy to use MongoDB query library. Congo is a pure header based library, making it easily portable as well as extremely lightweight. Congo uses exclusively MongoDB threadpools for all queries, making it an ideal choice for parallel and scalable ODM parsing.
The core way that Congo works, is by using a chainable interface, to find, insert, update and delete documents. This chainable interface uses standard threads, making it a familiar and easy way to interact with MongoDB with a low learning curve.
Please feel free to open an issue or PR. I'm available to answer any questions.