Observability

WebSocket connection count, Redis fan-out errors, send use-case latency, outbox lag (messaging has more relay workers than other schemas).

Logs are JSON in production. The correlation id is header X-Request-Id, MDC key traceId. Search in Grafana Logs (splick-logs) or Trace Explorer (splick-trace-explorer).

Prometheus scrapes /actuator/prometheus on this service port as part of the spring-apps job. Dashboards: Service Health, Use case health, Slow APIs, Async Pipeline.