Content delivery networks (CDNs) like Amazon CloudFront were, until recently, a relatively simple part of web infrastructure. Traditionally, web applications were designed around them, treating them mostly as a passive cache instead of an active component.

Lambda@Edge and similar technologies have changed all that and opened up a whole world of possibilities by introducing a new layer of logic between a web application and its users. Available since mid-2017, Lambda@Edge is a new feature in AWS that introduces the concept of executing code in the form of Lambdas directly on CloudFront’s edge servers.

One of the new possibilities that Lambda@Edge offers is a clean solution to server-side A/B testing. A/B testing is a common method of testing the performance of multiple variations of a website by showing them at the same time to different segments of the website’s audience.

#aws #testing #lambda@edge #a/b testing #aws lambda