Lumen OS: Building a Browser-Based Quant Trading Terminal Without React Frame Drops

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The author describes building Lumen OS, a browser-based quantitative trading workstation, to stream high-frequency market data at smooth 60 FPS. Incoming data rates of 200 to 500 events per second can cause React state updates to drop frames sharply, so the system routes WebSocket packets through an in-memory ring buffer that bypasses React reconciliation. The platform follows a local-first design, keeping telemetry, trade journals, and interface state in local memory for near-instant interaction. Access to its proxy backends is secured with Cloudflare Zero Trust using mutual service token verification. To reduce visual fatigue, it also uses a procedural Web Audio API synthesizer that sounds tones when large institutional bid walls are filled.

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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