Learn AWS Serverless Computing

Runtime API and bootstrapping

The Lambda service now provides a new runtime interface that helps us get more information about invocation events, and also allows us to submit an execution response. This functionality was made available when AWS released the ability to create a function using a custom runtime. This is where you can essentially bring your own language interpreter (a binary file or script), packaged in your deployment package or separately deployed as a Lambda layer. What this allows you to do is write your handler and logic in your preferred language, and then have this bootstrapped by Lambda.

In your code, you must implement the runtime API. This will allow you to interface to the Lambda service to send responses, send errors, ...