Bazel 10.0.0rc2 Released With Bzlmod Updates and Performance Enhancements
The latest Bazel release candidate introduces critical Bzlmod dependency management changes, performance optimizations for remote caching, and updated environment defaults.
Bazel 10.0.0rc2 is available for testing with updates to build configuration, external dependencies, and performance optimizations.
Bzlmod receives several updates. The bazel mod tidy command now evaluates all module extensions within the dependency graph, replacing bazel mod deps for lockfile consistency. Modules can no longer declare dependencies on themselves, and the root module cannot import overridden repositories through use_repo().
Performance additions include remote cache chunking via --experimental_remote_cache_chunking for large blobs and --remote_max_concurrency_per_connection to control concurrent gRPC requests in remote execution. Action rewinding via --rewind_lost_inputs is enabled by default to handle remote cache evictions.
Environment and tooling changes are included. The bundled JDK updates to version 27 and removes specific distrusted root CA certificates. The default PATH no longer includes /usr/local/bin. On Windows, launcher stubs now embed an asInvoker UAC manifest.
For configuration, the LC_CTYPE environment variable defaults to C.UTF-8 for actions using the default shell environment to ensure consistent behavior across Linux, macOS, and MSYS2. You can check the official release page for the full list of bug fixes.