CI/CD basics
Introduction
Nee code change pannina, manually build pannuva, manually test pannuva, manually deploy pannuva — ivlo effort! Oru typo fix panna kuda 30 minutes aagum. 😩
CI/CD vandha — code push pannina automatically build, test, deploy ellam nadakkum. Nee code la focus pannuva, baaki ellam automation paathukum!
Indha article la CI/CD fundamentals, GitHub Actions pipeline build pannradhu, AI project ku CI/CD setup — ellam hands-on ah paapom! ⚙️🚀
Continuous Integration (CI) Explained
Continuous Integration (CI) = Every code change automatic ah integrate, build, and test aagum.
Without CI 😰:
- Developer A — feature build panni 2 weeks la push
- Developer B — another feature build panni 2 weeks la push
- Merge conflicts! Bugs! 3 days fix panna pogudhu
With CI 😊:
- Developer A — small change push → auto build + test → ✅ pass
- Developer B — small change push → auto build + test → ✅ pass
- No conflicts! No surprises! Continuous ah integrate aagudhu
CI process:
Rule: Never push directly to main branch. Always use Pull Requests with CI checks! 🛡️
Continuous Delivery vs Deployment
CD has two meanings:
Continuous Delivery 📦:
- Code always ready to deploy
- But human manually approves deployment
- "Push button deploy" — one click deploy
- Best for: Sensitive apps (banking, healthcare)
Continuous Deployment 🚀:
- Code automatically deploys to production
- No human approval needed
- Every passing commit goes live
- Best for: Fast-moving apps, AI apps
| Aspect | Continuous Delivery | Continuous Deployment |
|---|---|---|
| Auto deploy? | ❌ Manual approval | ✅ Fully automatic |
| Risk | Lower | Higher |
| Speed | Fast | Fastest |
| Best for | Enterprise, regulated | Startups, AI apps |
AI apps ku recommendation: Continuous Deployment with canary releases — small percentage users ku first deploy, problems illana full rollout. 🎯
CI/CD Pipeline Architecture
┌─────────────────────────────────────────────────┐ │ CI/CD PIPELINE FLOW │ ├─────────────────────────────────────────────────┤ │ │ │ 👨💻 Developer │ │ │ │ │ ▼ git push │ │ ┌──────────┐ │ │ │ GitHub │──── Webhook Trigger │ │ └──────────┘ │ │ │ ┌────▼────┐ │ │ ┌─────── │ CI │ ───────┐ │ │ │ │ Server │ │ │ │ ▼ └─────────┘ ▼ │ │ ┌────────┐ ┌────────┐ ┌────────┐ │ │ │ Build │──▶│ Test │──▶│ Lint │ │ │ └────────┘ └────────┘ └────────┘ │ │ │ │ │ │ │ └────────────┼────────────┘ │ │ ┌──────▼──────┐ │ │ │ Docker Build│ │ │ └──────┬──────┘ │ │ ┌──────▼──────┐ │ │ │ Deploy │ │ │ ├─────────────┤ │ │ │ Staging ──▶ │ │ │ │ QA ──────▶ │ │ │ │ Production │ │ │ └─────────────┘ │ │ │ └─────────────────────────────────────────────────┘
GitHub Actions — Hands-On
GitHub Actions — most popular free CI/CD tool! 🎉
Why GitHub Actions?
- GitHub la direct ah integrated
- Free for public repos (unlimited)
- Private repos: 2000 min/month free
- YAML config — simple syntax
- Marketplace: 15,000+ pre-built actions
Basic concepts:
- Workflow = CI/CD pipeline definition (.yml file)
- Job = Set of steps that run on same runner
- Step = Individual task (checkout, build, test)
- Runner = Server that executes the job
- Trigger = Event that starts workflow (push, PR, schedule)
Folder structure:
Every .yml file = one workflow. Multiple workflows parallel ah run aagum! ⚡
Your First CI Pipeline
Basic CI pipeline for AI Python project:
Explained:
- Push or PR to main → trigger
- First job: Install deps, run tests, lint
- Second job: Build Docker image (only if tests pass)
Copy paste pannunga, modify pannunga — unga first pipeline ready! 🎯
AI Project CI/CD Extras
AI projects ku standard CI/CD plus extra checks venum:
1. Model Accuracy Check 🎯
2. Model Size Check 📦
3. Data Validation 📊
4. API Response Check 🔍
5. Model Version Tag 🏷️
Ivanga add pannina, AI-specific bugs early ah catch aagum! 🛡️
CI/CD Tools Comparison
Popular CI/CD tools compare:
| Tool | Free Tier | Hosting | Difficulty | Best For |
|---|---|---|---|---|
| GitHub Actions | 2000 min/mo | Cloud | Easy | GitHub users |
| GitLab CI | 400 min/mo | Cloud/Self | Medium | GitLab users |
| Jenkins | Unlimited | Self-hosted | Hard | Enterprise |
| CircleCI | 6000 min/mo | Cloud | Medium | Speed |
| Travis CI | Limited | Cloud | Easy | Open source |
| Azure Pipelines | 1800 min/mo | Cloud | Medium | Azure users |
My recommendation:
- 🥇 GitHub Actions — Beginners, most projects
- 🥈 GitLab CI — GitLab users, self-hosted option
- 🥉 Jenkins — Enterprise, maximum customization
Pro tip: Start with GitHub Actions. 90% projects ku ivlo podhum. Jenkins learn pannunga for interviews! 💼
CI/CD Best Practices
CI/CD pipeline effective ah irukka follow pannunga:
1. Fast Feedback ⚡
- Pipeline 10 min ku ulla complete aaganum
- Slow tests parallel ah run pannunga
- Cache dependencies (pip cache, Docker layer cache)
2. Branch Protection 🛡️
- Main branch ku direct push block pannunga
- PR mandatory, CI pass mandatory
- Minimum 1 reviewer approval
3. Environment Strategy 🌍
- Dev → Staging → Production
- Each environment separate config
- Production deploy only from main branch
4. Secrets Management 🔒
- API keys GitHub Secrets la store pannunga
- Never hardcode in YAML files
- Rotate secrets regularly
5. Notifications 🔔
- Slack/Teams notification on failure
- Email on deployment success
- Dashboard for pipeline status
6. Rollback Plan ↩️
- Every deploy rollback possible ah irukanum
- Previous version Docker image keep pannunga
- One-click rollback setup pannunga
Common CI/CD Mistakes
Beginners make pannra mistakes:
❌ No tests — CI pipeline irukku but tests illa. Useless!
❌ Too slow — 30+ min pipeline. Developers frustrated aagiduvaanga
❌ Ignoring failures — "CI failed but I'll merge anyway" — NEVER do this!
❌ Hardcoded secrets — API keys YAML la or code la — security risk
❌ No caching — Every run full install from scratch — waste time
❌ Complex pipeline — Over-engineered. Start simple, grow gradually
❌ No rollback — Deploy failed but previous version ku poga mudiyaadhu
❌ Skipping staging — Direct to production deploy — risky!
Golden rule: If CI fails, STOP. Fix it first. Don't accumulate broken builds. 🛑
Deployment Strategies
Production deploy panna different strategies:
1. Rolling Deployment 🔄
- Old servers one-by-one replace pannradhu
- Zero downtime
- Slow rollout
2. Blue-Green Deployment 🔵🟢
- Two identical environments
- Blue = current, Green = new
- Traffic switch pannradhu
- Instant rollback possible
3. Canary Deployment 🐤
- 5% traffic new version ku route
- Monitor pannunga
- Issues illana 100% ku rollout
- Best for AI apps — model performance test
4. A/B Deployment 🅰️🅱️
- Different versions different users ku
- Performance compare pannunga
- Data-driven decision
AI apps ku best: Canary deployment — new model 5% users ku serve pannunga, accuracy monitor pannunga, ok na full rollout. 🎯
Prompt: Create CI/CD Pipeline
Summary
Key takeaways:
✅ CI = Auto build & test on every code push
✅ CD = Auto deploy to staging/production
✅ GitHub Actions = Best free CI/CD tool for beginners
✅ AI extras = Model accuracy, size, data validation checks
✅ Best practices = Fast pipeline, branch protection, secrets management
✅ Deploy strategies = Canary best for AI apps
Action item: Innaiku oru simple GitHub repo create pannunga, GitHub Actions CI pipeline add pannunga. 30 minutes dhaan aagum — but career ku massive impact! 💪
Next article: Docker for AI Apps — containerization deep dive! 🐳
🏁 🎮 Mini Challenge
Challenge: Build Complete CI/CD Pipeline GitHub Actions
Real-world CI/CD pipeline setup — AI model inference app:
Step 1: AI Inference App Create Pannunga 🤖
Step 2: Unit Tests Write Pannunga ✅
Step 3: GitHub Actions Workflow Setup ⚙️
Step 4: Secrets Configure Pannunga 🔐
Step 5: Git Push & Monitor 🚀
Step 6: Slack/Email Notification 💬
Completion Time: 2-3 hours
Tools: GitHub Actions, Docker, FastAPI, pytest
Real-world applicable ⭐
💼 Interview Questions
Q1: Jenkins vs GitHub Actions vs GitLab CI — best choice?
A: Jenkins = self-hosted, powerful, learning curve high. GitHub Actions = GitHub native, easy, generous free tier. GitLab CI = GitLab native, good pipeline. Recommendation: GitHub Actions for startups/teams (GitHub already use), Jenkins for large enterprises (legacy systems).
Q2: Pipeline fail -> production deploy block — epdhi setup?
A: Branch protection rules: main la merge pannradhu, CI checks pass venum. Pull request required, code review required. Pipeline fail → automatic PR block. Manual override possible (admin-level). This ensures quality gate — bad code production la vappadhu illa.
Q3: Artifact vs Container — CI/CD la difference?
A: Artifact = build output (JAR, compiled binary, reports). Container = complete environment (code + dependencies + runtime). Containers better for scaling, consistency. Artifacts faster to generate. Modern practices: artifact generate, container build from artifact, registry push.
Q4: Pipeline optimization — slow runners problem?
A: Parallel jobs run (multiple tests parallel). Cache use (dependencies download, don't re-download). Smaller images (multi-stage Docker builds). Matrix strategy (multiple environments test simultaneously). Timeouts set (hung jobs kill). Critical metric = full pipeline execution time <5 minutes ideal.
Q5: Feature flags + CI/CD — why important?
A: Feature flags = feature control without code change. Deploy incomplete features → flag off (users see illa). Testing easy (flag on during testing). Gradual rollout (5% users → 50% → 100%). Rollback instant (no deployment needed, just toggle). Production deployment frequent (confidence high), but feature release controlled.
Frequently Asked Questions
Canary deployment na enna?