This repository includes shared code used to read and rewrite R source and binary package tarballs and ZIP archives without the overhead of temporary files and multiple passes. It supports:

• Reading and return DESCRIPTION information
• Modifying the DESCRIPTION file
• Extracting the package README
• Calculating both the original and resulting tarball SHA256 hashes.

This library is used by Posit Package Manager to extract README/DESCRIPTION data and rewrite packages internally for local and Git sources. It is also used by the Posit Package Service when creating CRAN and Bioconductor package snapshots.