Using Amazon AppConfig Agent with Amazon Lambda

An Amazon Lambda extension is a companion process that augments the capabilities of a Lambda function. An extension can start before a function is invoked, run in parallel with a function, and continue to run after a function invocation is processed. In essence, a Lambda extension is like a client that runs in parallel to a Lambda invocation. This parallel client can interface with your function at any point during its lifecycle.

If you use Amazon AppConfig feature flags or other dynamic configuration data in a Lambda function, then we recommend that you add the Amazon AppConfig Agent Lambda extension as a layer to your Lambda function. This makes calling feature flags simpler, and the extension itself includes best practices that simplify using Amazon AppConfig while reducing costs. Reduced costs result from fewer API calls to the Amazon AppConfig service and shorter Lambda function processing times. For more information about Lambda extensions, see Lambda extensions in the Amazon Lambda Developer Guide.