Lumen
Realtime analytics platform · 2026 · Lead engineer
A product analytics dashboard that answers questions about billions of events while you are still typing them.
Challenge
The previous dashboard took eight seconds to render a single chart. Analysts exported CSVs instead of using the product — the clearest signal that speed was the feature.
Approach
Moved aggregation to ClickHouse materialized views, streamed partial results over WebSockets and rendered charts on a WebGL canvas that stays at 60fps with a million points on screen.
Outcome
Median query time dropped below 120ms. Exports fell by 70% in the first month, and the dashboard became the first tab analysts open in the morning.
Results
- 2.1B events per day
- <120ms p50 query time
- −63% time to interactive
Next.js · TypeScript · ClickHouse · WebSockets · WebGL