Monitoring
Continuously observing system health (uptime, errors, performance) to detect issues before users do.
Monitoring is the practice of continuously observing system health: that it's online, responds quickly, isn't generating errors. The main dimensions are uptime, errors (count and types), latency (p50, p95, p99), and resource usage. Without monitoring, you find out about problems through user complaints. With good monitoring, you fix them before they're noticed. Spiralway implements monitoring from day one on every deploy.