zpaqlpy VS pixz

ZPAQ is the name of the tool but ZPAQ is also the name of the container format that gets used. ZPAQ embeds the decompression algorithm in the archive. One could store zstd-compressed blocks in ZPAQ archives as soon as a zpaql decompressor exists (e.g., for brotli there is a slow one implemented in a python subset and compiled to zpaql https://github.com/pothos/zpaqlpy).

I don't know exactly whether other formats are better for seeking and streaming, but since the baseline is tar, ZPAQ (in the 2.0 spec) is already better as it supports deduplication and files can even be updated append-only, and the compression is not an afterthought wrapped around it but well integrated.

That's really confusing since `pixz` exists and its "pixie" pronunciation actually works

https://github.com/vasi/pixz

pixz (https://github.com/vasi/pixz) is a nice parallel xz that additionally creates an index of tar files so you can decompress individual files. I wonder if dpkg could be extended to do something similar.

There's pixz, which indexes the tarball, allowing listing/extracting individual paths without decompressing the whole thing.

Also relevant is pixz [1] which can do parallel LZMA/XZ decompression as well as tar file indexing.

[1] https://github.com/vasi/pixz

Yes, it's as easy as installing pixz with symlinks pointing to xz (I think Debian even does this automatically as part of its post-installation scripts).

pixz - Parallel, indexed xz compressor. BSD-2-Clause

Not quite what you're asking, but if you're a 7-Zip fan and on Linux, you might be interested in pixz.