Observability

Comparable to: Datadog, Grafana, Honeycomb, Jaeger

Key Concepts

Use the concepts below when they fit the task. Not every worker needs custom spans or metrics.

• Built-in OpenTelemetry support across all SDKs — every function invocation is automatically traced
• The engine exports traces, metrics, and logs via OTLP to any compatible collector
• Workers propagate W3C trace context automatically across function invocations
• Prometheus metrics are exposed on port 9464
• registerWorker() with otel config enables telemetry per worker
• Custom spans via withSpan(name, opts, fn) wrap async work with trace context
• Custom metrics via getMeter() create counters and histograms

Architecture

The worker SDK generates spans, metrics, and logs during function execution. These flow to the engine, which exports them via OTLP to a collector (Jaeger, Grafana, Datadog). The engine also exposes a Prometheus endpoint on port 9464 for scraping.