The principles of modern perl pretty much boil down to "use the new stuff and turn off the old stuff":
* use strict and warnings, those go without saying. 'autodie' is also pretty much de rigueur these days too.
* disable legacy things like bareword filehandles and indirect object syntax.
* enable unicode everywhere by default in strings and I/O layers
* use Moose, or at least a compatible subset like Moo or Type::Tiny. This is probably the biggest differentiator of modern perl, as Moose is a major addition to the OO system, basically a backport of the perl 6 object system.
I wouldn't say the evolution of the language via modules is any kind of "faction", it's very much the mainstream thought of perl and always has been. Perl was designed from nearly the start to be hackable from within itself.
Also quite a few hits on CPAN: https://metacpan.org/search?q=modern%3A%3Aperl (ima convert all my old production code to Acme::Thoroughly::Modern::Perl tonight!)
For stability, Perl defaults to an old stable behavior. Modern features are opt-in Perl::Modern is a handy way to select a version, sort of like Python's `from future import foo`
Searching for "perl" will lead you to https://www.perl.org/