Zero to 1 Billion Records: A True Story of Learning and Scaling MongoDB at GameChanger` tells the story of how GameChanger, a company that provides scorekeeping and team management tools for amateur sports teams, scaled its use of MongoDB from a simple data layer to handle over 120,000 operations per second. The company's journey was marked by growing pains, including the limitations of their initial ORM implementation with Django, which led them to migrate to MongoDB. Through several iterations of their infrastructure, GameChanger learned how to decouple aggregation work from reads and writes, using asynchronous work queues and Redis to manage their pipeline. Their story is a great example for teams building apps on MongoDB, highlighting the importance of planning for scale and leveraging the expertise of MongoDB experts.