090 — CI/CD Pipeline {DevOps}

Purpose

Automate the build-lint-test-deploy lifecycle using GitHub Actions. Every commit is validated, every PR gets a preview deployment, and every merge to main triggers production deploy to Firebase. [EXPLICIT]

Physics — 3 Immutable Laws

1. Law of Pipeline as Code: The CI/CD pipeline lives in .github/workflows/ — versioned, reviewed, and tested like application code. No manual CI configuration. [EXPLICIT]
2. Law of Fast Feedback: Pipeline completes in under 10 minutes. Developers know pass/fail before context-switching. [EXPLICIT]
3. Law of Environment Parity: CI builds use the same Node version, npm version, and Firebase CLI version as local development. [EXPLICIT]

Protocol

Phase 1 — Pipeline Structure

1. Create .github/workflows/ci.yml with jobs: lint, test, build, deploy. [EXPLICIT]
2. Use matrix strategy for Node versions if supporting multiple. [EXPLICIT]
3. Cache node_modules via actions/cache keyed on package-lock.json hash. [EXPLICIT]
4. Run jobs in dependency order: lint → test (parallel with build) → deploy. [EXPLICIT]

Phase 2 — Firebase Deploy Integration

1. Generate Firebase CI token: firebase login:ci → store as FIREBASE_TOKEN secret. [EXPLICIT]
2. PR branches: firebase hosting:channel:deploy pr-${{ github.event.number }}. [EXPLICIT]
3. Main branch: firebase deploy --only hosting,functions --token $FIREBASE_TOKEN. [EXPLICIT]
4. Post preview URL as PR comment via actions/github-script. [EXPLICIT]

Phase 3 — Quality Gates in Pipeline

1. Lint: npm run lint — fail fast on lint errors. [EXPLICIT]
2. Test: npm run test:unit -- --coverage + firebase emulators:exec "npm run test:integration". [EXPLICIT]
3. Build: npm run build — fail if TypeScript errors or build warnings. [EXPLICIT]
4. Deploy: conditional on branch (main → prod, PR → preview). [EXPLICIT]

I/O

Input	Output
Git push / PR event	Pipeline execution (lint → test → build → deploy)
FIREBASE_TOKEN secret	Authenticated Firebase deploy
PR branch	Preview channel URL posted as comment
Main branch merge	Production deployment to Firebase

Quality Gates — 5 Checks

1. All jobs pass — no skipped required jobs at merge. [EXPLICIT]
2. Pipeline < 10 minutes — optimize or parallelize if exceeding. [EXPLICIT]
3. Secrets never logged — use ${{ secrets.* }}, never echo secrets. [EXPLICIT]
4. Branch protection — main requires passing CI + 1 approval. [EXPLICIT]
5. Deploy only from CI — no manual firebase deploy to production. [EXPLICIT]

Edge Cases

• Monorepo: Use path filters to run only affected package pipelines.
• Flaky tests in CI: Retry step with retry-action max 2 attempts. Investigate root cause.
• Firebase token expiration: Token doesn't expire, but rotate quarterly as best practice.
• Concurrent deploys: Use concurrency group to cancel outdated deployments.

Self-Correction Triggers

• Pipeline exceeds 10 min → profile steps, add caching, parallelize.
• Deploy fails → check Firebase token validity, project permissions, build output.
• PR missing preview URL → verify hosting:channel:deploy step and comment action.
• Secrets exposed in logs → rotate immediately, audit workflow for echo statements.

Usage

Example invocations:

• "/ci-cd-pipeline" — Run the full ci cd pipeline workflow
• "ci cd pipeline on this project" — Apply to current context

Assumptions & Limits

• Assumes access to project artifacts (code, docs, configs) [EXPLICIT]
• Requires English-language output unless otherwise specified [EXPLICIT]
• Does not replace domain expert judgment for final decisions [EXPLICIT]