high-perf-browser

# High Performance Browser Networking Framework A systematic approach to web performance grounded in how browsers, protocols, and networks actually work. Apply these principles when building frontend applications, setting performance budgets, configuring servers, or diagnosing slow page loads. ## Core Principle **Latency, not bandwidth, is the bottleneck.** Most web performance problems stem from too many round trips, not too little throughput. A 5x bandwidth increase yields diminishing returns; a 5x latency reduction transforms the user experience. **The foundation:** Every request passes through DNS resolution, TCP handshake, TLS negotiation, and HTTP exchange before a single byte of content arrives — each step adding round-trip latency. High-performance applications minimize round trips, parallelize requests, and eliminate unnecessary network hops. Understanding the protocol stack is the prerequisite for meaningful optimization. ## Scoring **Goal: 10/10.** When reviewing or building web applications, rate performance 0-10 based on adherence to the principles below. A 10/10 means full alignment with all guidelines; lower scores indicate gaps to address. Always provide the current score and the specific improvements needed to reach 10/10. ## The High Performance Browser Networking Framework Six domains for building fast, resilient web applications: ### 1. Network Fundamentals **Core concept:** Every HTTP request pays a latency tax — DNS lookup, TCP three-way handsh...