For decades, frontend performance has been guided by the simple principle that faster is better. We optimize load times, reduce latency, and remove every unnecessary delay from the user journey.
While building streaming AI interfaces with React, I discovered that traditional performance metrics do not tell the whole story. In AI products, users do not just experience a before and after. They experience a during. They watch responses stream in, follow reasoning traces, observe tool execution and form opinions about the system long before an answer is complete.
In this talk, I want to share lessons learned from building production AI experiences, including streaming architectures, rendering strategies and real-time interfaces. We will explore why time to first token, streaming consistency and the quality of the waiting experience can matter just as much as raw speed.
You will leave with practical insights for building AI-powered React applications and a new perspective on what performance means when users are watching the system think.
This talk has been presented at React Advanced 2026, check out the latest edition of this React Conference.
















