Building a Product with React Native

Konicek describes React Native’s JavaScript workflow, where code changes are bundled and the app restarts without waiting for a traditional compilation step. He valued having familiar JavaScript APIs across iOS and Android, along with a community of native libraries that developers could link into their apps.

To understand the experience of building a product, Konicek joined a team improving a Facebook feature that suggested posts advertisers could boost. The existing screen loaded the mobile website in a WebView, which was slow and looked different from the rest of the app. He rebuilt it as React Native UI, then ran the same JavaScript on iOS and Android, using shared helpers for platform-specific fonts, colors, and buttons.

A server-defined notification URL routed users to a React Native component in the Facebook app. Konicek used Relay and GraphQL to request page and post details, and GraphiQL to try queries and test new server fields. Sketch measurements and shared design components helped translate the visual layout, while conversations with the designer filled in interaction details such as animations.

Facebook released changes gradually: first to employees, then to small public groups, and eventually to everyone if crashes and product metrics looked acceptable. Server-side flags could disable a feature without a new app release, and an A/B test compared the new screen with the old one. The redesigned screen did not show a statistically significant improvement in the Boost Post metric, so Konicek moved closer to the original design and changed less at a time.

Konicek’s main lesson was to make small changes, measure them, and then decide what to try next. He also found that estimating, reproducing production errors, coordinating with a designer, and iterating on metrics all took time beyond writing the code.