Deployment workflows, CI/CD pipeline patterns, Docker containerization, health checks, rollback strategies, and production readiness checklists for web applications. Use when setting up CI/CD, containerizing an app, or checking production readiness before a release.

Deployment Patterns Production deployment workflows and CI/CD best practices. When to Activate Setting up CI/CD pipelines Dockerizing an application Planning deployment strategy (blue green, canary, rolling) Implementing health checks and readiness probes Preparing for a production release Configuring environment specific settings Deployment Strategies Rolling Deployment (Default) Replace instances gradually — old and new versions run simultaneously during rollout. Pros: Zero downtime, gradual rollout Cons: Two versions run simultaneously — requires backward compatible changes Use when: Standard deployments, backward compatible changes Blue Green Deployment Run two identical environments. Switch traffic atomically. Pros: Instant rollback (switch back to blue), clean cutover Cons: Requires 2x infrastructure during deployment Use when: Critical services, zero tolerance for issues Canary Deployment Route a small percentage of traffic to the new version first. Pros: Catches issues with real traffic before full rollout Cons: Requires traffic splitting infrastructure, monitoring Use when: High traffic services, risky changes, feature flags Docker Multi Stage Dockerfile (Node.js) Multi Stage Dockerfile (Go) Multi Stage Dockerfile (Python/Django) Docker Best Practices CI/CD Pipeline GitHub Actions (Standard Pipeline) Pipeline Stages Health Checks Health Check Endpoint Kubernetes Probes Environment Configuration Twelve Factor App Pattern Configuration Validation Rollback Strategy Instant Rollback Rollback Checklist [ ] Previous image/artifact is available and tagged [ ] Database migrations are backward compatible (no destructive changes) [ ] Feature flags can disable new features without deploy [ ] Monitoring alerts configured for error rate spikes [ ] Rollback tested in staging before production release Production Readiness Checklist Before any production deployment: Application [ ] All tests pass (unit, integration, E2E) [ ] No hardcoded secrets in code or config files [ ] Error handling covers all edge cases [ ] Logging is structured (JSON) and does not contain PII [ ] Health check endpoint returns meaningful status Infrastructure [ ] Docker image builds reproducibly (pinned versions) [ ] Environment variables documented and validated at startup [ ] Resource limits set (CPU, memory) [ ] Horizontal scaling configured (min/max instances) [ ] SSL/TLS enabled on all endpoints Monitoring [ ] Application metrics exported (request rate, latency, errors) [ ] Alerts configured for error rate threshold [ ] Log aggregation set up (structured logs, searchable) [ ] Uptime monitoring on health endpoint Security [ ] Dependencies scanned for CVEs [ ] CORS configured for allowed origins only [ ] Rate limiting enabled on public endpoints [ ] Authentication and authorization verified [ ] Security headers set (CSP, HSTS, X Frame Options) Operations [ ] Rollback plan documented and tested [ ] Database migration tested against production sized data [ ] Runbook for common failure scenarios [ ] On call rotation and escalation path defined

deployment-patterns