Send Notifications to Anyone

You can send Laravel Notifications not only to a certain user with $user->notify(), but also to anyone you want, via Notification::route(), with so-called "on-demand" notifications:

Notification::route('mail', '[email protected]')
        ->route('nexmo', '5555555555')
        ->route('slack', 'https://hooks.slack.com/services/...')
        ->notify(new InvoicePaid($invoice));