OSS Rebuild: Reproducible Builds to Harden Open Source
🔐 Google’s Open Source Security Team today announced OSS Rebuild, a new project to reproduce upstream artifacts and supply SLSA-grade provenance for popular package ecosystems. The service automates declarative build definitions and reproducible builds for PyPI, npm, and Crates.io, generating attestations that meet SLSA Build Level 3 requirements without requiring publisher changes. Security teams can use the project to verify published artifacts, detect unexpected embedded source or build-time compromises, and integrate the resulting provenance into vulnerability response workflows. The project is available as a hosted data set and as open-source tooling and infrastructure for organizations to run their own rebuild pipelines.