The AWS Serverless Application Model (AWS SAM) is a specification that extends AWS CloudFormation to provide a simplified syntax to express functions, APIs, and more. The latest SAM release supports four major updates and other features as detailed in the release notes.

from Recent Announcements https://aws.amazon.com/about-aws/whats-new/2019/10/aws-serverless-application-model-feature-support-updates-for-amazon-api-gateway-and-more/