Observability

Implement the three pillars of observability: logs, metrics, and traces.

The Three Pillars

Quick Pick

• Debug specific request? → Logs + Traces
• Alert on thresholds? → Metrics
• Understand system health? → All three
• Starting from zero? → Logs first, then metrics, then traces

Key Principles

• Use structured logging (JSON) with correlation IDs across all services
• Instrument the four golden signals: latency, traffic, errors, saturation
• Define SLIs/SLOs before building dashboards or alerts
• Alert on symptoms (user impact), not causes (CPU usage)

Quick Start Checklist

1. Set up structured logger (Pino recommended for Node.js)
2. Add request correlation IDs (middleware)
3. Instrument key metrics (RED: Rate, Errors, Duration)
4. Configure distributed tracing (OpenTelemetry)
5. Create dashboards for golden signals
6. Set up alerts with appropriate severity levels

References