devops / monitoring
Monitoring & Observability, Free
You can't fix what you can't see. Learn to instrument, monitor, and understand production systems with the open-source stack everyone uses — Prometheus, Grafana, and OpenTelemetry. All resources free and current.
Monitoring tells you when something is wrong; observability helps you understand why. The modern open-source stack is remarkably consistent: Prometheus collects metrics, Grafana visualizes them, and OpenTelemetry standardizes traces and logs across your services. Learn these and you can operate almost any system — plus the SRE principles that tell you what's actually worth alerting on.
01 · THE STACK
Metrics & dashboards
The open-source tools behind most production monitoring.
- Prometheus Documentation (official) ↗The de-facto standard for metrics and alerting in cloud-native systems — learn PromQL, exporters, and alerting rules.prometheus.io
- Grafana Documentation (official) ↗Turn metrics into dashboards and alerts — the visualization layer that sits on top of Prometheus and dozens of other data sources.grafana.com
- OpenTelemetry (official docs) ↗The open standard for traces, metrics, and logs — instrument your code once and send telemetry anywhere.opentelemetry.io
02 · WHAT TO MEASURE
The SRE approach
Which signals actually matter — from Google's reliability playbook.