90-devops-deployment

Deployment targets:

• Docker for packaging.
• AWS (ECS Fargate, Lambda, S3) for scalable cloud deployment.
• Vercel for frontend and serverless Next.js deployments.
• VPS (Ubuntu/Debian) for cost-effective long-running services.
• CI/CD for validation and release automation.

DevOps rules:

• Applications must be container-friendly.
• Keep builds reproducible.
• Use environment-driven configuration.
• Separate build-time config from runtime config.
• Add health checks where appropriate.
• Keep services stateless unless statefulness is intentional and documented.
• Ensure logs are structured and production-usable.

Docker expectations:

• Keep Dockerfiles clean and optimized.
• Prefer multi-stage builds when useful.
• Avoid baking secrets into images.
• Minimize image size where practical.
• Use .dockerignore to exclude node_modules, .env, .git, checkpoints.

AWS expectations:

• Prefer managed services where appropriate.
• Use least-privilege IAM policies.
• Make networking and environment assumptions explicit.
• Support observability via logs, metrics, and alarms.
• Design for rollback-safe deployments.

Vercel expectations:

• Use vercel.json for project configuration.
• Set environment variables via Vercel dashboard, never in code.
• Use Edge/Serverless functions for API routes.
• Keep build output under Vercel size limits.
• Use preview deployments for PR review.
• Configure custom domains and redirects in vercel.json.
• Use Vercel Analytics and Speed Insights where available.

VPS expectations:

• Use systemd or PM2 for process management.
• Set up Nginx/Caddy as reverse proxy with SSL (Let's Encrypt).
• Use UFW or iptables for firewall — only expose necessary ports.
• Set up unattended-upgrades for security patches.
• Use SSH keys only — disable password auth.
• Keep deployment scripted and repeatable (shell scripts or Ansible).
• Monitor with basic tooling: htop, journalctl, logrotate.

CI/CD expectations:

• Run lint, tests, and build validation before merge/deploy.
• Prevent obviously broken releases.
• Keep deployment config version-controlled.
• Use separate environments where needed, e.g. dev/staging/production.
• Use GitHub Actions for CI, Vercel for frontend CD, and scripts for VPS CD.

Do not:

• Hardcode AWS-specific IDs, Vercel tokens, or VPS IPs in code.
• Mix deployment-only hacks into application logic.
• Assume local-only paths/config in production code.
• Run services as root on VPS.
• Expose database ports publicly on any platform.