Transitioning to Appcraft: Evolution of Zalando’s Server-Driven UI Framework
Article Summary
Zalando powers 13 dynamic mobile pages without waiting for app store releases. Here's how they built a server-driven UI framework that ships changes same-day.
Zalando's mobile team evolved from their rigid TNA framework to Appcraft, a flexible server-driven UI system. The shift eliminated versioning headaches and enabled rapid iteration across iOS and Android using Elm architecture and Flexbox layout.
Key Takeaways
- Appcraft serves 13 dynamic pages including Zalando Stories with same-day deployment
- Elm architecture plus Flex unified iOS and Android layout paradigms
- Server-side versioning eliminated client coordination and backward compatibility issues
- Primitive components (Label, Button, Image) compose into complex UIs server-side
- Reduced MTTR during incidents and survived Cyber Week at scale
Critical Insight
By moving UI logic server-side with primitives and Flex layout, Zalando ships mobile UI changes instantly without app releases or cross-platform coordination.
