Andrei worked on the bazelbuild/bazel-central-registry repository, focusing on upgrading the Kotlin rules module to version 2.3.20 to improve Bazel compatibility and build reliability. He managed the dependency update by aligning with the official release notes and ensured the upgrade was implemented through precise Bazel configuration and version management. Andrei validated the stability of builds across the registry, reducing Kotlin-related integration issues and providing a safer upgrade path for downstream users. His work involved coordinating cross-repository changes, documenting the upgrade process, and utilizing skills in Bazel, dependency management, and Kotlin, demonstrating careful attention to build system robustness.