The backend for the Snapchat Stories feature includes Snapchat's largest storage write workload. Learn how we rebuilt this workload for Amazon DynamoDB and executed the migration. Safely moving such a critical and high-scale piece of the Stories infrastructure to a new system, right before yearly peak usage, led to interesting challenges. In this session, we cover data model changes to leverage DynamoDB strengths and improve both performance and cost. We also cover challenges and risks in making remote calls across cloud providers, dealing with issues of scale, forecasting capacity requirements, and how to mitigate the risks of taking an unproven system through the dramatic traffic spikes that occur on New Year's Eve.