TraceLens
Runtime truth engine for web applications — causality over metrics, AI-queryable.
What is TraceLens?
TraceLens transforms application debugging by focusing on causality rather than metrics. Instead of telling you "your app is slow," it builds real-time dependency graphs from browser and server runtime signals to show you exactly why it's slow.
It is self-hosted (your data never leaves your infrastructure), open-source under MIT, and integrates with AI coding assistants through the Model Context Protocol — so you can ask Claude or Kiro questions like "what are my app's current performance bottlenecks?" and get precise, grounded answers.
The most interesting design decision: TraceLens monitors its own dashboard performance in real time, so you experience the platform's capabilities before writing a single line of integration code.
Who is it for?
- Developers using AI coding assistants (Claude, Kiro, Cursor, Windsurf) who want grounded performance context
- Vibe-coding teams that don't want to wire up DataDog / New Relic just to see what's slow
- Teams who care about causality (why is this slow?) more than dashboards (here are 50 metrics)
- Anyone shipping browser apps where data privacy matters — TraceLens stays self-hosted
What does it do?
- Real-time dependency graph from browser + server runtime signals
- Critical-path detection (which exact call is blocking the response)
- Web Vitals + automatic performance instrumentation out of the box
- AI-queryable via MCP server — natural-language perf questions
- Self-monitoring meta-observability (the dashboard monitors itself)
- 5+ install modes: standard, quick, demo, enhanced, custom-port
- Localhost-first deployment — no cloud dependency
How is it built?
What makes it interesting?
- Builds real causality graphs, not just metric dashboards
- < 1 ms browser SDK overhead — you don't pay for the observability
- Reduces AI debugging cost by ~80% via precise MCP context
- Self-monitors the dashboard so you see it working before integrating
- MIT licensed and fully self-hostable
Want something like this for your business?
We adapt the patterns above to your stack on every engagement. The 15-minute discovery call is free — you leave with a plan regardless.