DynamoDB is a fully managed NoSQL database service that provides high throughput at low latency with seamless scalability. The service is the backbone for many Internet applications, handling trillions of requests daily. The scale of data that applications have to manage continues to grow rapidly, making it a challenge to manage systems and respond to events in real time. This talk will be a deep dive into the challenges of building the DynamoDB Streams feature, which provides a time-ordered sequence of item changes on DynamoDB tables, and leveraging it with AWS Lambda to reimagine large-scale applications for the cloud.