Designing Reliable Node.js Services

Reliability starts before production. The biggest wins usually come from boring defaults:

• strict timeouts for every outbound dependency
• idempotent handlers for retried events
• structured logs with request correlation ids

Baseline architecture

I use a thin HTTP layer, a service layer with pure business logic, and explicit adapters for storage and external APIs. That keeps testing fast and incidents easier to debug.

Operational checklist

1. Put SLOs on critical paths.
2. Track saturation and queue depth.
3. Run failure drills before launch.