Scaling React Native at Zalando: How Brownfield Migration Paid Off
Featuring
Watch the full webinar replay to see how Zalando’s engineers structured their brownfield migration and what lessons they shared for teams adopting React Native at scale. Here’s a recap if you’re more of a reader:
Why React Native and why now
Zalando’s mobile teams faced the limits of decade-old native architectures. Their business needed faster iteration, shared logic, and a unified platform experience. With an established internal framework, the Rendering Engine, built on React for web, React Native emerged as the natural fit. It allowed them to reuse existing knowledge, code, and developer skill sets across iOS, Android, and web.
Building consensus in a native world
Migrating an app at Zalando’s scale meant more than a technical shift. It required alignment across hundreds of engineers and multiple teams. The group approached this through extensive research, open communication, and a strong proof of concept. A POC built in 15 days demonstrated tangible results, showing React Native could integrate with Zalando’s Rendering Engine and run live in production without disruption.
The brownfield strategy
Zalando chose a brownfield approach: integrating React Native gradually into the existing app rather than rewriting it. Screens were rolled out one by one behind feature flags and A/B tests, starting with low-traffic areas to validate stability before expanding to complex, high-traffic screens. This de-risked the migration while maintaining business continuity.
A modular architecture for scale
The team built React Native as a self-contained SDK using dependency injection to communicate with native layers. This allowed React Native screens to live independently without inheriting legacy technical debt. On top of this, a cross-platform component library, powered by StyleX and React Strict DOM, enabled shared UI between mobile and web.
Results and next steps
The strategy proved itself: as of November 2025, four screens are fully live, twelve in testing, and seven more code-complete. Native teams have successfully shipped React Native screens (some as complex as the home screen) within weeks. By early 2026, Zalando expects 90% of app traffic to run on React Native.
Next on the roadmap: deeper observability, list performance optimizations, debt cleanup, and continued open-source collaboration.
