Why Meta is moving its android apps from java to kotlin

Engineers at Facebook parent meta have detailed their multi-year effort to convert the codebases from java to kotlin

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That's a large task for a company with thousands of web developers and android developers

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The migration is underway, with Meta's android app which consists of 10 million lines of code

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Meta's switch from Java to kotlin for android application development is a milestone

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Despite the benefits of kotlin that motivated Meta's switch but still there are some demerits that make the move risky

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Firstly, there is a large gap in popularity between Java and kotlin ,this includes the complexity and interoperability

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Kotlin is a popular programming language but compared to java the popularity gap is clear.

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Here the biggest concern with Meta's switch is that slower build times in Kotlin versus Java

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Meta engineers have decided to convert almost all their codebases into Kotlin rather than writing new code using kotlin

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There is good news for budding developers as well. The Meta has released several in-house Kotlin conversion tools on GitHub

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A Facebook engineer detailed last year, that while Kotlin adaption can be smooth, it is difficult at scale

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So far, Meta has on average seen an 11% reduction in the size of its codebase.

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The Google Home Team has reported a 33% reduction in its app codebase while migrating

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Google's Kotlin product manager says we are so excited to see Meta make the move to Kotlin and are glad they've had success.

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