CloudFormation Concepts

AWS CloudFormation is a declarative tool for provisioning AWS infrastructure. Templates are written in YAML or JSON and deployed as stacks.

What It Does Well

• Automates AWS resource creation.
• Supports disaster recovery and repeatable environment creation.
• Makes infrastructure changes reviewable like application code.
• Helps copy patterns across regions or environments.

Core Concepts

• Template: the declarative definition of infrastructure.
• Stack: the deployed instance of a template.
• Stack set: a way to manage stacks across accounts or regions.
• Parameters: runtime inputs to a template.
• Outputs: values exported after creation.
• Resources: the AWS objects created by the stack.

Template Sections

• AWSTemplateFormatVersion
• Description
• Parameters
• Resources
• Outputs

Practical Notes

• Use parameters for values that differ between environments.
• Keep templates small and composable when possible.
• Treat stack outputs as the contract between infrastructure layers.