LobstersSunday · May 17, 2026FREE

Content-defined chunking in Bazel's remote cache

BuildBuddy announced the integration of content-defined chunking (CDC) into its remote cache for Bazel, detailed in a blog post published on May 17, 2026. This enhancement aims to significantly improve the efficiency of remote caching by intelligently segmenting files. Unlike traditional fixed-size chunking, which divides files into arbitrary blocks, CDC identifies natural boundaries within file content using rolling hashes. This ensures that small, localized changes to a file, such as inserting a line of code or modifying a comment, only affect a minimal number of chunks rather than shifting all subsequent fixed-size blocks. This approach is particularly beneficial for large source files or generated artifacts where minor edits would otherwise invalidate entire fixed-size blocks, forcing a re-upload of the whole file to the remote cache, even if only a few bytes changed. For Bazel users, this directly addresses a common pain point where small, frequent code modifications can lead to disproportionately large cache invalidations and slow remote cache synchronization. The implementation is designed to reduce redundant data transfers, minimize storage requirements, and substantially increase cache hit rates, thereby accelerating build times and reducing network egress costs for projects utilizing Bazel with BuildBuddy's remote caching services. This feature is now available to users of the BuildBuddy platform.