Extract from a war story created while optimizing the performance of one our internal applications (3.4s to 140ms). This core presentation focuses on: working with the (great!) Chrome React Profiler extension and fallback to Profiler when you need to continue optimizing when there are no more clear performance targets. Once the performance culprits have been identified with the profiler, we dive into the implementation: useMemo, memo and reselect to avoid unnecessary rerenders. All this, sprinkled with some common performance guidelines and considerations.