Today AWS is announcing the public preview of AWS Serverless Application Model CLI (AWS SAM CLI) support for local development and testing of AWS Cloud Development Kit (AWS CDK) projects. AWS SAM and AWS CDK are both open-source frameworks for building applications using infrastructure as code (IaC). AWS SAM is template-based using JSON or YAML, while the AWS CDK uses languages such as Python or Node.
Before today, you could use the AWS SAM CLI to build locally, test, and package serverless applications defined using AWS CloudFormation or AWS SAM templates. With this preview release, you can use AWS SAM CLI to build, test, and in the future, package applications defined using the AWS CDK.
Support for the AWS CDK is currently in preview and the team is asking for your feedback and submissions. The goal is for both communities to help improve the local development process using AWS SAM CLI. No bug is too small. No feature request is too large to submit to the open source repository.
https://docs.aws.amazon.com/cdk/v2/guide/best-practices.html