5 Reasons Why N26 Is Moving to Kotlin
Article Summary
Pat Kua from N26 shares how the fintech company moved from Java to Kotlin for backend services. Their pragmatic, incremental approach turned a language migration into a productivity win.
N26, a mobile banking platform, evaluated multiple languages including Scala and TypeScript before settling on Kotlin. The engineering team formed an interest group, ran experiments during their 'Get Stuff Done Days,' and carefully validated concerns before rolling out the change across their backend services.
Key Takeaways
- Kotlin's incremental learning curve made engineers productive quickly without steep ramp-up
- Opinionated syntax eliminates style debates, letting teams focus on business domain
- Java interop enables gradual migration: teams started with Kotlin tests first
- Google's Android support expanded the ecosystem and enabled cross-team knowledge sharing
- 10% of repositories converted to Kotlin through structured rollout plan
Critical Insight
N26 successfully adopted Kotlin by validating it incrementally through experiments and small production deployments, proving language migrations don't require big-bang rewrites.
