Express LensUltra-Fast HTTP Observability & APM Suite

Zero-dependency HTTP monitoring, percentile latencies (p50/p90/p95/p99), Prometheus exporter, slow request profiler, and embedded web dashboard for Node.js, Bun, Deno, and Edge.

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Multi-Framework Ecosystem

Native subpath adapters for Express, Fastify, Hono (Bun, Deno, Cloudflare Workers), and Next.js App Router.

Real-Time Web Dashboard

Built-in dark mode dashboard UI with Server-Sent Events (SSE) live streaming and instant cURL generation.

Prometheus & Grafana Ready

Serves standard Prometheus Exposition text at /metrics for seamless metric scraping.

True Percentile Latencies

Real-time sliding window calculations for p50, p90, p95, and p99 response times.