How We Made Carousell's Mobile Web Experience 3x Faster
Article Summary
Stacey Tay from Carousell reveals how her team achieved a 3x speed improvement on mobile web—and turned it into a 63% traffic surge. The secret? A ruthless performance budget and smart PWA architecture.
Carousell, a Southeast Asian classifieds marketplace, faced a critical challenge: their mobile web took over 15 seconds to load on 3G networks in Indonesia and the Philippines. The team spent 6 months building a performance-first Progressive Web App to serve users with slower devices and unreliable internet.
Key Takeaways
- Set strict 120KB budget for critical resources, 2s First Contentful Paint limit
- Route-based code splitting plus service workers reduced repeat load times dramatically
- 63% organic traffic increase in Indonesia, 3x boost in ad click-throughs
- Flow typing and design system enabled fast iteration without breaking things
- Automated bundlesize checks in PRs enforced performance budget religiously
Critical Insight
By implementing a performance budget and PWA best practices, Carousell cut mobile web load time by 67% and saw immediate gains in user engagement and conversions.
