pkgtarzst

Pkgtarzst is a hypothetical packaging format designed to optimize software distribution by packaging files in a tar archive that is compressed with the Zstandard algorithm. The term is a portmanteau of pkg, tar, and zst. It is not an official standard and has appeared primarily in theoretical discussions about packaging efficiency and modern compression.

Pkgtarzst files have a single extension, .pkgtarzst. The archive combines two layers: a metadata block and a tar payload. The header includes package name, version, architecture, dependencies, and a checksum or digital signature. The tar payload contains the filesystem layout to be installed, along with per-file metadata if needed. Tools decompress the zstd layer and then apply the tar extraction, preserving file attributes. Some designs allow embedded scripts to run before or after installation.

Advantages include reduced package size thanks to Zstandard’s compression and fast decompression, which can speed up install times. The tar-based payload preserves standard Unix filesystem semantics, such as permissions and symlinks. Concerns include tooling compatibility, as pkgtarzst support requires both tar and zstd tooling, and potential limitations around incremental updates and patching compared to delta or binary packaging formats.

Pkgtarzst remains a theoretical concept or proposal rather than an implemented standard. While some packaging ecosystems may experiment with tar-zstd combinations, no mainstream deployment formally adopts pkgtarzst as of now.