This repository contains CPAN index files for old perls.
For some reasons, you might have to use old perls, such as v5.8 or v5.10. Then you'll have difficulty installing CPAN modules because a lot of CPAN modules requires a more recent perl.
In cases like this, the index files in this repository might help.
Let's say you use perl v5.10.1, and want to install Plack. Plack now requires perl v5.12, so it cannot be installed as is:
❯ perl -v
This is perl, v5.10.1 (*) built for darwin-2level
❯ cpm install Plack
...
FAIL install Plack-1.0051
However, if you specify the index file 5.10.1.txt, you should be able to install Plack on perl 5.10.1:
❯ cpm install --resolver 02packages,https://raw.githubusercontent.com/skaji/perl-cpan-index-legacy/main/5.10.1.txt,https://cpan.metacpan.org Plack
...
DONE install Plack-1.0050
53 distributions installed.
Which modules will you be able to install? See NOTE.md.
https://www.nntp.perl.org/group/perl.perl5.porters/2023/04/msg266308.html