Engineering insights on observability, distributed tracing, and production debugging.
Find Django N+1 queries with query-count tests and request traces. Fix lazy relation loads with select_related or prefetch_related.
Measure Node.js response time by route, read p95 latency with traces, and separate event loop delays from database and API waits.
Learn when Sentry performance units still apply, how legacy transactions were counted, and why current span quotas need a different estimate.
Monitor FastAPI routes with request metrics and OpenTelemetry traces. Check latency, errors, and downstream work before setting alerts.
Set ELASTIC_APM_TRANSACTION_SAMPLE_RATE, check why it seems ignored, and map the setting to OpenTelemetry sampling during a migration.
Set DD_TRACE_SAMPLE_RATE in Node.js, understand rate limits and sampling rules, and verify which distributed traces reach Datadog.
Set up FastAPI tracing with OpenTelemetry. Connect request, SQLAlchemy, and HTTPX spans, then verify trace context across services.
Track rogue LLM calls with traces, call counts, token usage, costs, models, and retry evidence before a loop becomes an incident.
Set up trace based alerts for errors and latency. Check sampling, request counts, time windows, and notification context before paging.
Migrate to OpenTelemetry without downtime with a parallel Collector path, trace parity checks, and a safe service-by-service cutover.
Monitor LLM call latency in production workflows with traces, model percentiles, token usage, costs, errors, and workflow context.
