By default non-brewed cpan modules are installed to the Cellar. If you wish
for your modules to persist across updates we recommend using `local::lib`.
You can set that up like this:
PERL_MM_OPT="INSTALL_BASE=$HOME/perl5" cpan local::lib
And add the following to your shell profile e.g. ~/.profile or ~/.zshrc
eval "$(perl -I$HOME/perl5/lib/perl5 -Mlocal::lib=$HOME/perl5)"