Moose

“Moose is essentially a language extension for Perl 5 that
provides a modern, elegant, fully featured object system. I say
“language extension”, but Moose is written in pure Perl, and as
you’ll see, its syntax is still normal Perl. You don’t need to
patch Perl itself to use Moose; under the hood, it’s just Perl
5.

Because Moose is still just Perl 5, it’s fully compatible with
all of those wonderful modules on CPAN, regardless of whether they
are written in Moose (and most aren’t, as CPAN has been around for
so long, and Moose is relatively new).

Complete
Story