package BasicRole;

use Moo::Role;

has 'attrib' => ( is => 'ro' );

sub do_something {
   ...
}

1;

package NotSoBasicRole;

use Moo::Role;
with 'BasicRole';

has '+attrib' => ( is => 'ro', default => sub { return 1; } );

1;

package SpecialRole;

use Moo::Role;
with 'NotSoBasicRole';

has '+attrib' => ( is => 'ro', default => sub { return 2; } );

sub do_something_else {
   ...
}
1;

package App;
use Moo;
with 'BasicRole';

1;

package AnotherApp;
use Moo;
with 'SpecialRole';
1;

package main;
use v5.10;
no warnings;

my $app = App->new();
say $app->attrib;

my $another_app = AnotherApp->new();
say $another_app->attrib;