CI/CD Pipeline Architecture

A well-designed CI/CD pipeline is the backbone of engineering velocity, yet many teams cobble together fragile pipelines that become the biggest source of developer frustration. In this challenge, you will design a complete CI/CD pipeline that takes code from commit to production with automated quality gates, security scanning, and instant rollback capabilities. The pipeline uses CodePipeline as the orchestrator with CodeBuild for build and test stages, but the architecture is tool-agnostic in its patterns. Source stage triggers from CodeCommit (or GitHub via CodeStar Connections) on push to main, with branch protection requiring pull request reviews. The build stage runs in CodeBuild with a custom Docker image containing all build tools, producing versioned artifacts stored in S3 with lifecycle policies. Testing stages run in parallel: unit tests, integration tests against a DynamoDB Local instance, and security scanning using CodeGuru Reviewer for code quality and ECR image scanning for container vulnerabilities. The deployment strategy uses CodeDeploy with blue/green deployments for ECS services and canary deployments for Lambda functions. You will design the promotion flow: dev deploys automatically, staging requires integration test pass, and production requires manual approval plus a canary period with automated rollback on CloudWatch alarm triggers. The rollback mechanism uses CodeDeploy's automatic rollback on alarm, with a custom Lambda function that captures the deployment context for post-incident analysis. The architecture also includes a self-service pipeline factory using CDK constructs, allowing teams to spin up new pipelines from a template. This challenge teaches deployment strategy design, quality gate implementation, and the operational patterns that enable safe, fast releases.