$thing->break if $thing->isa("Fragile");

##</code><code>##

package MyApp::Plugin::Stage1 { use Role::Tiny };
package MyApp::Plugin::Stage2 { use Role::Tiny };

package MyApp::Plugin::Frobnicate {
   use Role::Tiny::With;
   with "MyApp::Plugin::Stage2";
}

...;

foreach my $plugin ($self->plugins)
{
   # The "DOES" method is like "isa", but checks roles
   # instead of checking inheritance.
   #
   if ($plugin->DOES("MyApp::Plugin::Stage2")) {
      $plugin->activate($self);
   }
}