Thanks for the clarifications around the libarchive business.

The problem is that this patch still does not work because
python-libarchive-c does not support zstd, which
python-conda-package-handling needs.  I don't understand how upstream
does this.  I've reported it upstream:

https://github.com/conda/conda-package-handling/issues/14

My knowledge of python is not enough to understand if upstream is wrong
or if I'm using python-libarchive-c incorrectly.

-- 
Pierre Neidhardt
https://ambrevar.xyz/