Test::Modern provides the best features of Test::More, Test::Fatal, Test::Warnings, Test::API, Test::LongString, and Test::Deep, as well as ideas from Test::Requires, Test::DescribeMe, Test::Moose, and Test::CleanNamespaces. Test::Modern also automatically imposes strict and warnings on your script, and loads IO::File. (Much of the same stuff Modern::Perl does.) Although Test::Modern is a modern testing framework, it should run fine on pre-modern versions of Perl. It should be easy to install on Perl 5.8.9 and above; and if you can persuade its dependencies to install (not necessarily easy!), should be OK on anything back to Perl 5.6.1.