Prometheus

Open-source monitoring and alerting toolkit — the de facto standard for cloud-native monitoring.

Prometheus is an open-source systems monitoring and alerting toolkit originally built at SoundCloud and now a CNCF graduated project, forming the de facto standard for cloud-native monitoring. It collects and stores time series data using a dimensional data model where metrics are identified by name and rich key-value labels, enabling powerful queries via PromQL. Prometheus scrapes metrics from instrumented applications over HTTP via a pull model, auto-discovers scrape targets through service discovery integrations for Kubernetes, Consul, EC2, and others, and evaluates alerting rules to trigger notifications. Its architecture is designed for reliability — each Prometheus server is standalone and self-contained. With a massive ecosystem of exporters, client libraries in over a dozen languages, and seamless integration with Grafana for visualization, Prometheus powers observability for millions of applications worldwide.