2.3. Implementing CI/CD for Applications with AWS Developer Tools
💡 First Principle: Every code change should flow through an automated pipeline — from commit to production — with testing at every stage. Manual deployments are the enemy of reliability.
What happens when a developer pushes directly to production without CI/CD? One bad commit takes down a live application, and there's no automated way to roll back. AWS provides a suite of tools — CodePipeline, CodeBuild, CodeDeploy — that chain together to create automated, repeatable, auditable deployment pipelines.
Think of CI/CD like an assembly line — similar to how Toyota revolutionized manufacturing: raw materials (code) enter one end, get tested and assembled at each station (build, test, staging), and only finished products (validated releases) reach customers. If any station detects a defect, the line stops. Without this automation, every deployment is a manual, error-prone gamble.
The DVA-C02 tests your ability to configure and troubleshoot this pipeline — expect questions about buildspec.yml, appspec.yml, deployment strategies, and pipeline stage failures.
The infrastructure travels the same path: keep the SAM or CloudFormation templates in the same repository as the code, so infrastructure changes are reviewed, tested and deployed by the same pipeline (see 2.1.3). Each stage authenticates through its IAM service role (the CodeBuild or CodePipeline service role), never through access keys stored in environment variables.
