canary-releases

## What I do - Design and implement canary release strategies - Gradually shift traffic from stable to new versions - Implement automated traffic routing based on metrics - Create canary analysis and evaluation frameworks - Build rollback triggers based on error rates and latency - Monitor and analyze canary performance metrics ## When to use me - When you want to reduce risk of new deployments - When you need to validate changes with real production traffic - When deploying to large user bases where failures are costly - When you want data-driven deployment decisions - When implementing progressive delivery practices - When working with microservices architectures ## Key Concepts ### Traffic Splitting ```yaml # Kubernetes Istio virtual service for canary routing apiVersion: networking.istio.io/v1alpha3 kind: VirtualService metadata: name: myapp spec: hosts: - myapp http: - route: - destination: host: myapp subset: stable weight: 90 - destination: host: myapp subset: canary weight: 10 ``` ### Metrics-Based Routing ```javascript // Prometheus alert for canary analysis - alert: CanaryHighErrorRate expr: | rate(http_requests_total{service="canary"}[5m]) / rate(http_requests_total{service="stable"}[5m]) > 0.1 for: 5m labels: severity: critical annotations: summary: "Canary error rate exceeds 10% of stable" description: "Automated rollback recommended" ``` ### Phased Rollout 1. **Initial**: 1-5% traffic to canary 2. **Validation**: Monitor error rates and latency 3. **Expansion**: Increase to 25%, 50%, 75% 4. **Promotion**: Full 100% traffic 5. **Cleanup**: Remove old version ### Key Metrics to Monitor - **Error Rate**: Compare canary vs. stable - **Latency**: P50, P95, P99 response times - **Success Rate**: Request completion percentage - **Resource Usage**: CPU, memory, network - **Business Metrics**: Conversion rates, session duration - **Custom Metrics**: Domain-specific indicators ### Rollback Triggers - Error rate exceeds 2x stable environment - P99 latency exceeds threshold (e.g., 500ms) - CPU or memory usage exceeds 80% - Custom business metric degradation - Manual override triggered