Black Friday is one of the most challenging times for any system, as traffic can increase by four to ten times within a short period. Teams often prepare by running performance tests, but they may not be using the right testing method.
In this talk, I will present a real-life situation where a system seems fine during testing but crashes when faced with actual conditions.
The main problem isn't the system itself, but the way the test was set up.
This topic is especially important for teams developing and expanding web applications, especially during high-traffic events like Black Friday.
It bridges the gap between performance testing strategies and real-world system performance, while also considering business impact.
This talk has been presented at JSNation 2026, check out the latest edition of this JavaScript Conference.




















