Step-by-step articles on Observability, part of our Infrastructure collection.
Showing 10 articles
Monitoring tells you that something is wrong. Observability helps you understand why , including for problems you didn't predict. It's built from three kinds of telemetry. Metrics: numbers over time http_requests_total{route="/checkout", status="500"} 1243 htt...
OpenTelemetry's auto-instrumentation patches popular libraries (http, Express, pg, Redis, fetch and many more) so you get traces with almost no code changes. Zero-code setup npm install @opentelemetry/api @opentelemetry/auto-instrumentations-node export OTEL_S...
In a system of many services, one slow user request might pass through an API gateway, three services, a queue, two databases and a third-party API. Distributed tracing reconstructs that whole path. Traces and spans A trace is the full journey of one request,...
console.log("user " + id + " failed") is fine on a laptop. In production you need logs that machines can search and filter: JSON with consistent fields, levels and request IDs. Basic setup import pino from 'pino'; export const logger = pino({ level: process.en...
Prometheus is the most widely used open-source metrics system. Your app exposes current values on a /metrics endpoint, and Prometheus scrapes them every few seconds and stores them as time series. The metric types Counter - only goes up (resets on restart): re...
You can measure thousands of things. These three well-known frameworks tell you which handful matter most. The four golden signals From Google's SRE book, for any user-facing system: Latency - how long requests take. Track successful and failed requests separa...
"Make it reliable" isn't a goal you can measure. Service level objectives turn reliability into a number that product and engineering can agree on. The terms SLI (indicator) - a measurement of user experience, usually a ratio of good events to total events. Ex...
Apps can send telemetry straight to a vendor, but most production setups put an OpenTelemetry Collector in between. It receives data from many sources, processes it and exports it to one or more backends. Why use a Collector Apps only need to know one endpoint...
When alerts fire constantly, people stop reading them, and the one that matters gets missed. Good alerting is mostly about deciding what not to page on. 1. Every page must be urgent and actionable Ask: "If this fires at 3 a.m., does someone need to do somethin...
LLM features fail in new ways: answers get worse without any error, costs spike because a prompt grew, an agent loops through tools. Normal API monitoring doesn't catch these, so add LLM-specific telemetry. 1. Usage and cost const response = await client.messa...
