Continuous Integration & Continuous Delivery (CI/CD) 🚀

Continuous Integration (CI) is the practice of merging all developer working copies to a shared mainline several times a day with automated build and test verification. Continuous Delivery (CD) ensures software can be reliably released to production at any time.

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1. The Modern CI/CD Pipeline Architecture

flowchart LR
    Dev["Developer Git Commit"] --> CI_Lint["Linting & Static Analysis\n(Prettier, ESLint, ShellCheck)"]
    CI_Lint --> CI_Build["Compile & Unit Tests\n(Fast feedback < 5m)"]
    CI_Build --> CI_Sec["Security Scan\n(SAST, Secrets, Trivy)"]
    CI_Sec --> CI_Package["Immutable Package / OCI Image\n(Docker, Cosign Sign, SBOM)"]
    CI_Package --> CD_Staging["Deploy to Staging / Preview"]
    CD_Staging --> CD_Integration["Integration & E2E Testing"]
    CD_Integration --> CD_Prod["Progressive Production Rollout\n(Canary / Blue-Green / GitOps)"]

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2. Core Pillars of Production Pipelines

1. Build Once, Deploy Everywhere

Never rebuild an artifact or container image for different environments. Build a single, immutable container image or binary in the CI stage, sign it, and promote the exact same digest (sha256:...) through Dev, Staging, and Production by altering external configuration (ConfigMaps / Secrets).

2. Fast Feedback Loops (< 10 Minutes)

If a pipeline takes 45 minutes to run, developers stop waiting for results and context-switch:

• Cache dependencies (node_modules, Go module cache, Docker layer cache via GitHub Actions type=gha).
• Parallelize independent test suites (matrix strategies).
• Run fast unit tests first; defer heavy integration/E2E tests to staging promotion gates.

3. Ephemeral Environments & Preview Apps

Modern CI spins up isolated preview environments per Pull Request (e.g., using Kubernetes namespaces or Vercel/Cloudflare preview URLs) allowing full end-to-end testing before merging to main.

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3. Topics & Guides

• 🧱 Pipeline Design — Stages, build once and promote, test strategy, speed, security and flaky tests
• 🚦 Deployment Strategies — Rolling, blue-green, canary, shadow, feature flags and rollback
• 🏷️ Release and Versioning — Versioning schemes, immutable artifacts, promotion and changelogs
• 📈 DORA Metrics — Measuring delivery performance
• ⚙️ GitHub Actions Deep Dive — Reusable workflows, composite actions, matrix builds, runner security, and OIDC federation
• 🌿 Git Strategy & Best Practices — Trunk-based development, conventional commits, rebase workflows, and signing
• 🔐 DevSecOps Curriculum — 20-module end-to-end security pipeline from SAST to runtime defense
• ☸️ GitOps with Argo CD — Declarative deployment and automated sync on Kubernetes

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Related Knowledge Bases

• 🔐 DevSecOps Security Controls — Pipeline hardening and supply chain
• ☁️ AWS ECS Deployment — Blue-green deployments via CodeDeploy
• 🐧 Shell Scripting — Automation scripting for CI runners

Across the wiki

• CD Integration — CI/CD pipelines (Kubernetes)
• AWS CodePipeline for EKS — CI/CD pipelines (Kubernetes)
• Tekton Pipelines — CI/CD pipelines (Kubernetes)
• CD — CI/CD pipelines (Kubernetes)