Install Guix by TUI should enable to configure source mirror

[雨宮美羽]

I am from China. My network environment isn’t really good. And I am
installing Guix several hours till now. It is still downloading a large
amount of packages with turtle speed. I don’t know when it will done. When
installing Arch Linux, users can customize the source of Pacman, so that we
can set it to mirrors that deployed in China. Thus the installing speed can
be accelerated. But when I install Guix with the TUI installer, there is no
way to do like that. Result in slow installing speed and sometimes failed
installing packages. So I hope some developers can enhance the TUI
installer to solve this problem. Thanks!