You don't. @system is the set of things that are required for the basic function of Gentoo.
However, @system does not include nano. It includes virtual/editor which depends on app-editors/nano, vim, gvim, xemacs, etc. so install vim and portage will remove nano at your next depclean.
However, I really wouldn't recommend it. If things go really wrong vim can break but nano is very hard to break so it is excellent to have around for emergencies.
First things first, but not necessarily in that order.
Apologies if I take a while to respond. I'm currently working on the dematerialization circuit for my blue box.
The Doctor wrote:However, @system does not include nano. It includes virtual/editor which depends on app-editors/nano, vim, gvim, xemacs, etc. so install vim and portage will remove nano at your next depclean.
I set vim as system editor without problem, remeber to activate vim with eselect editor and eselect vi
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