Recently, we shipped an optimization to our global routing service that reduced its memory usage by 15%, improved time-to-first-byte (TTFB) from the 75th percentile and above by 10%, and significantly improved routing speeds for websites with many static paths. A small number of websites, with hundreds of thousands of static paths, were creating a bottleneck that slowed down our entire routing service. By replacing a slow JSON parsing operation with a Bloom filter, we brought path lookup latency down to nearly zero and improved performance for everyone. Link to heading The path lookup operation When you make a request to a Vercel deployment, our routing service first checks whether the requested path exists before attempting to serve it. This prevents unnecessary requests to storage and protects against enumeration attacks , where attackers try to discover hidden files by guessing URLs.…