Lambda@Edge is a service from AWS that allows executing code close to the user’s actual location. It combines the benefits of the Function-as-a-Service Lambdas with the global availability of their content delivery network CloudFront. Together they provide ease of development and maintenance paired with low latency and high availability. This combination of business code and Infrastructure-as-Code in the same project makes it quite challenging to stay on top of the testing, especially when changes to either are co-dependent.

After multiple years of development and testing, I’ve developed battle-proven strategies and patterns to tackle this complex setup. We start with understanding the structure and key challenges when dealing with Lambda@Edge. Keeping the cloud edge computing challenges in mind, I show you how to design your tests in a multi-layer structure to reach an efficient and wholesome coverage. And to wrap things up, we look at code changes and match them up with the test design.

All of this is transferable to other cloud providers.