This is my general approach when I need to do something similar, in this case, a poor man's Module::Pluggable system:

# NOTE! This is just a snippet from a larger work shown only to illust
+rate the principle

use strict;
use warnings

use Cwd ();
use Try::Tiny;

# used to find the location of THIS module. assumes that all plug-ins
# will be under a directory named after this module (without the '.pm'
+)
sub _basename_dir {
    my $class = shift;

    # In this case, we want to always use THIS package's name, not a s
+ub-class
    my $package = __PACKAGE__;
    
    $package =~ s/::/\//g;
    my $packpath = $INC{ join( '.', $package, 'pm' ) };
    $packpath =~ s/\.pm$//;
    
    my $realpath = Cwd::realpath($packpath);
    
    return $realpath;
}

# be sure to get the method in THIS package, not a sub-class
my $basedir = __PACKAGE__->_basename_dir();
my $pdir = "$basedir/Plugin";

opendir( my $dh, $pdir)or die "Can not open $pdir";
my @plugins = grep { /\.pm$/ && -f "$basedir/Plugin/$_" } readdir($dh)
+;
closedir( $dh ) or die "Can not close $pdir";

for my $plugin ( @plugins ) {
    my $ppkg = try {
        my $package = __PACKAGE__;

        # gotta change from '::' to '/' so require is happy.
        $package =~ s/::/\//g;
        my $ppath = join( '/', $package, 'Plugin', $plugin);
        require $ppath;
        
        # and now we change back to normal '::' without the .pm to use
+ as a class name.
        $plugin =~ s{(?:\.pm)$}{};
        my $pname = join( '::', __PACKAGE__, 'Plugin', $plugin );
        
        return ($pname->isa( __PACKAGE__ ) && $pname->_enabled) ? $pna
+me : undef ;  
    }
    catch {
        warn "Invalid plugin: $plugin\n$_\n";
        return;
    } or next;
     
    $ppkg->register();
}
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There are probably better or cleaner ways to do this (this is Perl, after all) but this has been a very stable approach for me.