New comment by tornaria on void-packages repository

https://github.com/void-linux/void-packages/pull/34030#issuecomment-967770614

Comment:
Second draft:
 - rename pkg from sage to sagemath (please remove sage before installing sagemath as I didn't set replaces=)
 - updated sage to sage-9.5.beta6
 - now it builds in place at `/usr/lib/sage-$version`
 - the resulting pkg includes a lot of useless stuff that comes with the distribution; we'll have to clean up. E.g. SAGE_ROOT/upstream is definitely unnecessary (1.2G); possibly SAGE_ROOT/pkgs or at least SAGE_ROOT/pkgs/sagemath-standard/build (2.6G).

A useful reference is https://github.com/sagemath/binary-pkg.

Now it's possible to run tests on the installed sage, for instance:
```
$ sage -tp 8 --all
```
to test all with 8 parallel jobs.