How do you ensure a web app can handle thousands of concurrent users?

“Scalability is architected from day one through serverless infrastructure, auto-scaling groups and CDN edge caching on AWS. We implement load balancing, database read replicas and asynchronous processing for resource-intensive operations. Every deployment includes stress testing against projected traffic peaks. The result is an application that maintains sub-second response times whether serving 100 or 100,000 simultaneous users.”