Perl 5's twofold approach to solving this mess is to use compile time checks to manage new features. The use VERSION syntax lets you specify a version of perl. The feature pragma lets you enable or disable new features on a case by case basis. In my experience, this works really well.

The feature pragma (see https://perldoc.perl.org/feature.html) lets you manage new features on an individual basis. You just write: feature NAME_OF_FEATURE;. For example, feature signatures; In this case adding subroutine/method signature support. This is a compile time check.

If you don't want to hassle with enabling features on a piecemeal basis, you can also specify a version of perl you wish to rely on with use VERSION (see https://perldoc.perl.org/functions/use.html). For example, if want all of the standard features of perl 5.26.1, you say use v5.26.1.