The Lambda Runtime Interface Emulator is a proxy for Lambda’s Runtime and Extensions APIs, which allows customers to locally test their Lambda function packaged as a container image. It is a lightweight web-server that converts HTTP requests to JSON events and maintains functional parity with the Lambda Runtime API in the cloud. It allows you to locally test your functions using familiar tools such as cURL and the Docker CLI (when testing functions packaged as container images). It also simplifies running your application on additional computes. You can include the Lambda Runtime Interface Emulator in your container image to have it accept HTTP requests instead of the JSON events required for deployment to Lambda. This component does not emulate Lambda’s orchestrator, or security and authentication configurations. You can get started by downloading and installing it on your local machine. When the Lambda Runtime API emulator is executed, a /2015-03-31/functions/function/invocations endpoint will be stood up within the container that you post data to it in order to invoke your function for testing. There are a few ways you use the Runtime Interface Emulator (RIE) to locally test your function depending on the base image used.