How does Meta use Kotlin to improve the reliability of their codebase and their developer experience?

How does Meta use Kotlin to improve the reliability of their codebase and their developer experience?

Android Development at Meta has been Kotlin-first for almost three years now.

Eve Matthaey, Engineer Kotlin journey at KotlinConf’24:

- Meta's Android team has introduced 20 million lines of Kotlin to their codebase since shipping the first line of Kotlin five years ago.
- Adopting Kotlin has improved the reliability of their codebase and made it more concise, realizing at least a 10% reduction in lines of code.
- Kotlin build speeds are a dominating factor for a great developer experience, and incremental compilation is key for having a quick feedback loop.