Core Build is Uber’s centralized build platform team. We own the common build infrastructure — Bazel, Gazelle, build rules, client-side remote build caching and execution, and shared build/test CI pipelines — across Uber’s Java, Go, Android, iOS, and Web monorepos.
Our vision is simple: make builds fast with less friction. Because the stack is shared, an improvement we make once benefits every engineer at Uber.
We work across three pillars:
Velocity:
Make builds faster everywhere with fewer resources — in CI, remote development environments, and on laptops — through caching, remote execution, sharding, and build-graph optimization.
Reliability & Diagnosability:
A build failure should never leave an engineer stranded. Every failure should communicate what failed, how to fix it, and who can help.
Modernization, Unification & Scale:
Keep the platform on the latest Bazel, maximize CI fleet utilization with smart test selection and build-graph pruning, and apply GenAI/ML to automate diagnosis and optimization.
Our next major initiative is to stop compiling the same code thousands of times: make mobile builds remote-first, so a local build becomes a download rather than a compile, and run only the tests a change can actually affect.