Folks preparing for system design — read this real Cloudflare outage & learn why resilience matters

If you're preparing for system design Design, here’s a real-world lesson worth studying. On 18th Nov, a tiny database permission change at Cloudflare silently broke assumptions… and took down **

If you're preparing for system design Design, here’s a real-world lesson worth studying. On 18th Nov, a tiny database permission change at Cloudflare silently broke assumptions… and took down 20% of the internet for nearly 4 hours. It wasn’t a DDoS attack. It was one missing filter in a SQL query. 📌 Good read for anyone preparing for system design interviews or building distributed systems: <a href="https://roundz.ai/blog/postmortem-deep-dive-cloudflare-november-2025-outage)