Part 2 of a series on optimizing Gradle builds in ephemeral CI environments focuses on the Configuration phase. Benchmarks on a Spring Boot project show that caching the `modules-2` dependency directory cuts build time by 28% (31.5s → 22.7s). The shared read-only dependency cache via `GRADLE_RO_DEP_CACHE` delivers identical savings while allowing multiple ephemeral runners to share one pre-populated cache without lock contention. Caching compiled Kotlin DSL scripts (`kotlin-dsl`) saves an additional 10%, with gains scaling up for larger multi-module builds. Caching processed JARs (`jars-9`) alone yields no measurable benefit. The post also covers how `setup-gradle` GitHub Action and Develocity's Universal Cache automate these optimizations without manual Dockerfile maintenance.
