Upgrading from source code in Whonix-Qubes

Hello, I am still learning about Whonix and Kicksecure, I have read this documentation:
/wiki/Dev/Build_Documentation/Upgrading_Derivative_Deb_Packages_from_Source_Code#Get_the_Source_Code
and decided to try the same on my cloned test Whonix-ws, in Qubes OS, but i got a huge amount of errors.
Based on the page on the wiki, it looks like Qubes templates are not designed for this? If so, how can I help develop this in Qubes templates?

That script might be generally broken. Unspecific to Qubes-Whonix.

Step 1), please send patches to make that script work in an App Qube.
(Yes, non-persistent but we can discuss doing it in a Qubes Template later.)