Endpoint health monitoring system that runs concurrent checks against 10 services (HTTP APIs, webhooks, database connections) using asyncio. Each check measures response time at p50/p95/p99 percentiles, tracks uptime over 24h windows, and triggers alerts when thresholds are crossed. Failed checks retry with exponential backoff (1s, 2s, 4s) before marking an endpoint degraded. Supports HTTP, TCP, and DNS protocols. The dashboard shows a real-time status board with per-endpoint heatmaps, incident timeline, and aggregate uptime. Built with Python + FastAPI + asyncio/aiohttp. Designed to run as a lightweight self-hosted alternative to commercial monitoring tools.