
In this talk from Callstack’s React Universe Meetup in San Francisco, Tim Golen, Director of Engineering at Expensify, shares how his team rethought React Native performance tracking, not by chasing TTI or FPS, but by asking: what actually matters to our users?
You’ll hear how they defined meaningful KPIs, how they measure them with StatsD, and how they visualize trends and regressions using Grafana dashboards. Tim also covers why blindly optimizing all interactions is a waste, and what to measure instead.
What you’ll learn:
- How to define UX-focused performance goals
- Which metrics Expensify tracks across versions, platforms, and envs
- How to avoid the trap of measuring what’s easy, not what’s useful
- How they use performance data to prioritize and iterate weekly
- How Rock-powered remote builds help them ship fixes 90% faster
If you’ve ever struggled to tie performance work back to user impact, this talk gives you a smarter strategy.
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