Learning about the past of nested stacks
As infrastructure scales, engineers face the challenge of maintaining an increased load with a reasonable amount of effort. For example, a team may need to deploy the same application across multiple AWS regions or accounts. For that, they can use StackSets and manage the same infrastructure using granular rollouts and rollbacks.
Another example of scale is the stack itself. While provisioned in a single stack, a template can grow in size and turn into a multi-thousand-line YAML or JSON file, thus becoming hard to maintain.
One example of maintaining scale is the Transform macro, which we explored in the previous section, but this macro requires engineering effort to maintain an AWS Lambda function and, at some point, will become backwards-incompatible. Therefore, we need sustainable ways to introduce modularity to the template and allow independent updates for each part of the stack.
The CloudFormation development team built two features...