How do you ensure observability in serverless applications?

Observability is critical in serverless applications for monitoring ephemeral, event-driven functions (such as AWS Lambda), supporting fault diagnosis, performance optimization, and security compliance scenarios.

The core pillars include logs (recording outputs), metrics (quantifying resource usage), and traces (mapping call chains). Integrated tools like OpenTelemetry or cloud services (such as AWS CloudWatch) provide end-to-end visibility, improving debugging, cost management, and scaling decisions.

Implementation steps: Configure log export to centralized storage, set metric alert thresholds, and enable distributed tracing tools. A typical scenario is debugging stateless function calls, with business values including reduced downtime, optimized resource utilization, and enhanced user experience.