CI/CD in the Cloud

CI/CD in the Cloud

Continuous Integration and Continuous Delivery automate the path from code to production. Instead of manually deploying servers and applications, you define everything as code and let the cloud handle the rest. Faster releases, fewer bugs, less stress.

The CI/CD Pipeline

  ┌──────────────────────────────────────────────────────────┐
  │                    CI/CD PIPELINE                        │
  │                                                          │
  │   CODE       BUILD       TEST       DEPLOY     MONITOR  │
  │                                                          │
  │  ┌─────┐   ┌─────┐   ┌─────┐   ┌─────┐   ┌─────┐     │
  │  │     │──▶│     │──▶│     │──▶│     │──▶│     │     │
  │  │ Git │   │Compile│   │Unit │   │Prod │   │Alerts│     │
  │  │Push │   │Package│   │Integ│   │Stag │   │Logs  │     │
  │  │     │   │Build  │   │E2E  │   │Blue/│   │Metr  │     │
  │  └─────┘   └─────┘   └─────┘   │Green│   └─────┘     │
  │                                 └─────┘                 │
  │                                                          │
  │  Trigger:    Every        Every       Manual/   Always  │
  │  git push    commit       merge       auto      running │
  └──────────────────────────────────────────────────────────┘

AWS CodePipeline

AWS CodePipeline orchestrates your release workflow. You define stages like source, build, and deploy. Each stage pulls from or pushes to AWS services like CodeCommit, CodeBuild, and CodeDeploy. It's like assembly line automation for your software.

  ┌────────────────────────────────────────────────────┐
  │              AWS CODEPIPELINE                       │
  │                                                    │
  │  ┌──────────┐    ┌──────────┐    ┌──────────┐    │
  │  │  Source   │───▶│  Build   │───▶│  Deploy  │    │
  │  │          │    │          │    │          │    │
  │  │CodeCommit│    │CodeBuild │    │CodeDeploy│    │
  │  │S3/GitHub │    │          │    │          │    │
  │  └──────────┘    └──────────┘    └──────────┘    │
  │       │               │               │           │
  │       ▼               ▼               ▼           │
  │  ┌──────────┐    ┌──────────┐    ┌──────────┐    │
  │  │  Source  │    │  Build   │    │  Deploy  │    │
  │  │  Output │    │  Output  │    │  to EC2/ │    │
  │  │  Artifct│    │  Artifact│    │  ECS/Lambd│    │
  │  └──────────┘    └──────────┘    └──────────┘    │
  └────────────────────────────────────────────────────┘

GitHub Actions

GitHub Actions lets you build CI/CD workflows right in your repository. Define YAML files in .github/workflows/ and trigger them on push, pull request, or schedule. It connects to cloud providers for deployment.

  name: Deploy to AWS
  on:
    push:
      branches: [main]

  jobs:
    deploy:
      runs-on: ubuntu-latest
      steps:
        - uses: actions/checkout@v4
        - name: Configure AWS credentials
          uses: aws-actions/configure-aws-credentials@v4
          with:
            aws-access-key-id: ${{ secrets.AWS_KEY }}
            aws-secret-access-key: ${{ secrets.AWS_SECRET }}
        - name: Deploy to S3
          run: aws s3 sync ./build s3://my-bucket

Deployment Strategies

How you release matters as much as what you release. Different strategies minimize risk and downtime.

  ┌────────────────────────────────────────────────────────┐
  │            DEPLOYMENT STRATEGIES                        │
  │                                                        │
  │  Rolling Update          Blue/Green                    │
  │  ┌───┬───┬───┬───┐      ┌───┬───┐ ┌───┬───┐          │
  │  │v1 │v1 │v2 │v2 │      │OLD│OLD│ │NEW│NEW│          │
  │  └───┴───┴───┴───┘      └───┴───┘ └───┴───┘          │
  │  Gradual replace          Swap traffic instantly       │
  │                                                        │
  │  Canary                   A/B Testing                  │
  │  ┌───┬───┬───┬───┐      ┌───┬───┬───┬───┐            │
  │  │v1 │v1 │v1 │v2%│      │v1 │v2 │v1 │v2 │            │
  │  └───┴───┴───┴───┘      └───┴───┴───┴───┘            │
  │  Small % gets new ver    Route by header/cookie        │
  │                                                        │
  │  Feature Flags           Immutable Infrastructure     │
  │  ┌──────────────────┐   Replace entire environment    │
  │  │ Code checks flag  │   instead of updating in place │
  │  │ ON  → new feature │   Use CloudFormation/Terraform │
  │  │ OFF → old behavior│                                 │
  │  └──────────────────┘                                 │
  └────────────────────────────────────────────────────────┘

Infrastructure as Code (IaC)

Your infrastructure should be versioned, testable, and repeatable. IaC tools like CloudFormation, Terraform, and CDK let you define servers, networks, and databases in code files. No more clicking through consoles.

  # Example: Terraform to create an S3 bucket
  resource "aws_s3_bucket" "data" {
    bucket = "my-app-data-bucket"

    tags = {
      Environment = "production"
      ManagedBy   = "terraform"
    }
  }

  resource "aws_s3_bucket_versioning" "data" {
    bucket = aws_s3_bucket.data.id
    versioning_configuration {
      status = "Enabled"
    }
  }

Pipeline Best Practices

  [x] Run automated tests before every deployment
  [x] Use separate environments for dev, staging, and prod
  [x] Store secrets in a vault (SSM Parameter Store, Secrets Manager)
  [x] Implement rollback mechanisms for failed deploys
  [x] Use immutable artifacts — don't rebuild for each environment
  [x] Monitor deployments with CloudWatch and alarms
  [x] Keep pipeline definitions as code (version controlled)
  [x] Run security scans (Snyk, SonarQube) in the build stage