If you are using Build.PL define the {requires}{perl} = VERSION field. If you are using MakeMaker (Makefile.PL) you should upgrade ExtUtils::MakeMaker to 6.48 and use MIN_PERL_VERSION parameter. Perl::MinimumVersion can help you determine which version of Perl your module needs.

Add a META.json to the distribution. Your buildtool should be able to autogenerate it.

Move your *.pm files in a directory named 'lib'. The directory structure should look like 'lib/Your/Module.pm' for a module named 'Your::Module'. If you need to provide additional files, e.g. for testing, that should not be considered for Kwalitee, then you should look at the 'provides' map in META.yml to limit the files scanned; or use the 'no_index' map to exclude parts of the distribution.

Error: mylib/Devel/AssertOS.pm, mylib/Devel/AssertOS/Cygwin.pm, mylib/Devel/AssertOS/MSWin32.pm, mylib/Devel/CheckOS.pm

Add =head1 LICENSE and/or the proper text of the well-known license to the main module in your code.

Add 'use warnings' (or its equivalents) to all modules, or convince us that your favorite module is well-known enough and people can easily see the modules warn when something bad happens.

Error: Devel::AssertOS, Devel::AssertOS::Cygwin, Devel::AssertOS::MSWin32, Devel::CheckOS

Ask the owner of the distribution (the one who released it first, or the one who is designated in x_authority) to give you a (co-)maintainer's permission.

Error:

• Devel::AssertOS
• Devel::AssertOS::Cygwin
• Devel::AssertOS::MSWin32
• Devel::CheckOS

Split the distribution, or fix the version numbers to make them consistent (use the highest version number to avoid version downgrade).

Error: 1.0,1.1,1.14,1.42

Add all modules contained in this distribution to the META.yml field 'provides'. Module::Build or Dist::Zilla::Plugin::MetaProvides do this automatically for you.

Add a 'repository' resource to the META.yml via 'meta_add' accessor (for Module::Build) or META_ADD parameter (for ExtUtils::MakeMaker).

This is not a critical issue. Currently mainly informative for the CPANTS authors. It might be removed later.