Meta Pascal Hartig

How Meta is Translating Its Java Codebase to Kotlin

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Android

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Pascal Hartig from Meta sits down with the engineers tackling one of Android's biggest migration challenges: converting tens of millions of lines of Java to Kotlin. How do you pull off a transformation this massive without breaking everything?

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More on Rewrite You Don't Need a Rewrite: Expo's New Brownfield React Native Story Expo Oct 12, 2026 More from Meta Translating Java to Kotlin at Scale Meta Dec 18, 2024 Also on Android Building Arrive's Confetti in React Native with Reanimated Shopify Jun 12, 2026

This page summarizes “How Meta is Translating Its Java Codebase to Kotlin” by Meta, published Feb 25, 2025. All credit for the original work goes to the authors.

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