Thanks. I guess it's https://metacpan.org/pod/Moose
"The main goal of Moose is to make Perl 5 Object Oriented programming easier, more consistent, and less tedious. With Moose you can think more about what you want to do and less about the mechanics of OOP." Wouldn't think this would be required for problem authors.
I'll update the documentation concerning the need to load Math:Complex for certain types of problems. There might be analogous requirements for other situations.