CloudFormation

CloudFormation is the declarative layer under almost everything else AWS offers for infrastructure as code — the CDK, SAM, Service Catalog and StackSets all end up producing or deploying CloudFormation templates. Understanding stacks, change sets and the intrinsic functions therefore pays off well beyond CloudFormation itself.

Start with CloudFormation for templates, stacks, StackSets, change sets, stack policies and the practices that keep a template maintainable. !Ref versus !GetAtt covers the two intrinsic functions that connect resources to each other, which is the first thing that trips people up. CloudFormation examples holds worked snippets: mappings, a VPC, an Auto Scaling group, a load balancer and a database.

For how CloudFormation compares with the CDK, SAM and Service Catalog, see the IaC options.