Observability

Seeing inside a running system: metrics and time-series storage, range queries and downsampling, alerting, and the cardinality that decides whether it all fits in memory.

Explainers

• Design a Metrics & Monitoring System — Why billions of measurements a day outgrow an ordinary database and need a purpose-built one — the compression tricks that make the data fit, the label explosion that can sink the whole system, and an alerting pipeline that watches itself.