Upgrading Meta's Kotlin Infrastructure to K2

on YouTube ↗26m

" summary

Meta upgrades Kotlin front end to K2 across a heavy Buck-based Android toolchain, migrating 95% of models and achieving 20% faster builds on average. Migration requires rewriting compiler plugins to use FIR extensions, adding FIR transformers and declaration generators to modify in-memory IR, and switching KSP to a standalone KSP2 invocation. Challenges include a 20 million line Kotlin codebase, stricter type checks that expose latent bugs, and custom casabi source-only symbol generation.

AI-written summary · about

" chapters (8)

1. 0:00Kotlin K2 migration intro
2. 1:51Why Meta started K2
3. 6:06K2 migration challenges
4. 9:47K2 compiler front end
5. 12:21K2 compiler plugins
6. 17:26Build speed with K2
7. 23:38KSP and K2 at Meta
8. 25:08K2 adoption results

" related talks

• 35mK2 compiler in productionSergei Rybalkin · droidcon New York 2024
• 42mKotlin Adoption in the Giant Java ApplicationSergei Rybalkin · droidcon New York 2022
• 35mAt long last we have Kotlin first at Meta!Sergei Rybalkin, Peng Jiang · droidcon London 2022
• 33mMeta-programming with KSP and Kotlin compiler pluginsTadeas Kriz · droidcon New York 2022
• 38mHow Kotlin 2.0 Will Evolve Android Developmentdaasuu · DroidKaigi 2024
• 43mCompile Kotlin faster with ABISergei Rybalkin · droidcon Berlin 2023
• 23mKotlinLisa Watkins · Mobile @Scale 2023
• 44mMeta-programming with KSP and Kotlin compiler pluginsTadeas Kriz · KotlinConf 2023