Back to Blog
Technical Deep Dive
9 min read

Making Serverless Observability Actually Useful

Jason Miller
Senior Backend Developer
February 10, 2025
Serverless
Observability
AWS

Serverless computing unlocks faster deployments and automatic scaling, but it comes with a frustrating downside — lack of visibility. You deploy a function, it runs, and disappears. When something breaks, you're left combing through scattered logs and cryptic error traces.

The Pain of Flying Blind

At our company, we moved large parts of our API layer to AWS Lambda. Everything looked great—until it wasn't. Latency spikes, cold starts, and partial outages began to creep in, and without real-time observability, diagnosing them felt like shooting in the dark.

How We Solved It

We adopted a layered observability approach:

  • OpenTelemetry for instrumentation across Lambda, API Gateway, and external services.
  • Custom trace IDs injected at the edge and passed across all services to track end-to-end flow.
  • CloudWatch Logs Insights for quick aggregations, enhanced with AWS X-Ray for request mapping.

Pro Tips

  • Use telemetry SDKs in every Lambda function. Even simple logs help.
  • Aggregate metrics by cold start vs warm start to catch performance regressions.
  • Alert on absence of logs — missing logs often mean your function didn't trigger at all.

Cost Considerations

Observability in serverless isn't free. More metrics and logs = more cost. We trimmed our log size by 30% by removing verbose dev-mode outputs and using structured JSON logs instead.

The Real Win

Within two weeks of rolling this out, our MTTR (Mean Time to Recovery) dropped by 40%. Teams had more confidence, and onboarding new developers became easier with visual traces showing exactly what each function was doing.

Serverless doesn't have to mean blind. With the right tools and mindset, observability becomes your superpower — not a tradeoff.

Jason Miller
Senior Backend Developer