They use the word "Reproducible Builds" for linking the VCS commit to PyPI's repacked source code upload, that's why "reproduce the source code" sounds a little confusing.
For projects with native bindings you can still fairly trivially solve this with SBOMs, and some Linux distributions are doing this for many years now. The compiler is a dependency that needs documenting, and they explicitly write they need means to re-create the documented environment from that SBOM.
For projects with native bindings you can still fairly trivially solve this with SBOMs, and some Linux distributions are doing this for many years now. The compiler is a dependency that needs documenting, and they explicitly write they need means to re-create the documented environment from that SBOM.