package Karl::Constructor {

    use Role::Tiny;
    use feature qw(say);

    say __PACKAGE__;

    sub new {
        my ( $class, $self ) = @_;
        bless $self, $class;
        $self;
    }

    1;
}

package CarConstructor {

    use feature qw(say);
    use Role::Tiny;
    use Role::Tiny::With;
    with qw(Karl::Constructor);
    requires qw(brand model color hp price);

    say __PACKAGE__;

    1;
}

package CarConfigurator {

    use Role::Tiny::With;
    use feature qw(say);

    with qw(CarConstructor SomePlugin);

    say __PACKAGE__;

    sub brand {
        shift->{brand};
    }

    sub color {
        shift->{color};
    }

    sub hp {
        shift->{hp};
    }

    sub price {
        shift->{price};
    }

    sub model {
        shift->{model};
    }

    1;
}

package SomePlugin {

    use Role::Tiny;
    use feature qw(say);

    say __PACKAGE__;

    before brand => sub { say q(Tricky Dick!) };

    around brand => sub {
        uc &{ (shift) };
    };

    after brand => sub {
        say q(Too late!);
    };

    sub extra {
        shift->{extra};
    }

    1;
}

#!/usr/bin/env perl

use strict;
use warnings;
use CarConfigurator;
use feature qw(say);

say __PACKAGE__;

my $car = CarConfigurator->new(
    {
        brand => q(Porsche),
        color => q(Black),
        model => q(911),
        hp    => q(>300),
        price => q(Don't ask),
        extra => q(Wine),
    }
);

say qq(Brand:\t), $car->brand;
say qq(Model:\t), $car->model;
say qq(Color:\t), $car->color;
say qq(hp:\t),    $car->hp;
say qq(Price:\t), $car->price;
say qq(Extra:\t), $car->extra;

__END__

karls-mac-mini:playground karl$ ./run.pl
Karl::Constructor
CarConstructor
SomePlugin
CarConfigurator
main
Tricky Dick!
Too late!
Brand:	PORSCHE
Model:	911
Color:	Black
hp:	>300
Price:	Don't ask
Extra:	Wine