How to make Kotlin compile 2x faster
summary
Large monorepo (≈5 million lines, ~1,000 modules, ~6,600 Android engineers, ~6k builds/day) cuts Kotlin compile time by changing concrete things: remove unused dependencies and flatten task graph, move plugin declarations into the module that needs them, split big modules and use SPI/DI to reduce upstream rebuilds, and pack Kotlin incremental intermediates into the cache as a baseline cache so cached outputs become incremental-ready. Result: Kotlin compiler cache hits rise ~30% → ~90%, average build time drops 30–70% (full build ~20min → 3–4min). class path isolation modularize and single-responsibility
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chapters (11)
- 0:00Introduction
- 2:50Build speed importance
- 4:35Beyond hardware upgrades
- 7:23Gradle cache basics
- 9:29Unused dependencies removal
- 12:20Modularizing projects
- 19:09Classpath isolation
- 27:16Custom cache packs
- 30:29Baseline cache
- 34:29Optimization summary
- 36:57Q&A
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