Edge runtimes excel at auth gates, geo routing, and lightweight transforms — not heavy database aggregation. We keep edge handlers under 50ms CPU and push complex logic to regional Node workers.
Cold starts show up as tail latency on low-traffic routes. Warmup pings and synthetic checks per region catch regressions before customers do.
Secrets and environment parity differ from traditional servers — document which vars are edge-safe and rotate them on a separate cadence.
Distributed tracing across edge and origin is still immature; we correlate with request IDs propagated in headers end to end.
Load test from multiple regions — a fast Virginia response does not help your APAC users.
