Teams often discover outages only after customer complaints, missing critical response time. A monitoring service like StatusD solves this by probing services on a schedule. Built with Go, it checks HTTP, TCP, and DNS endpoints, detects failures, and triggers alerts to channels like Slack or Teams. The system also tracks incidents automatically and exposes metrics for Prometheus and Grafana.

The application uses a worker pool to handle concurrency, ensuring efficient probing of multiple services simultaneously. It employs a registry pattern for probes, allowing easy extension to new protocols. PostgreSQL stores probe results and incident data, while a state machine manages the transition between UP and DOWN states. This prevents false alarms from transient network issues.

Deploying the entire stack is straightforward with Docker Compose, which orchestrates the Go app, database, metrics collector, and dashboard. Configuration is managed through JSON files, defining which assets to monitor and where to send notifications. This setup provides a proactive, self-hosted alternative to commercial monitoring tools, giving teams full control over their service health checks.