Using Postmark for bulk mail is currently in beta. Before start sending campaigns via Postmark we highly recommend getting in touch with their support and let them know you want to start sending bulk emails.
#Handling Mailgun feedback in an existing Laravel app
You should only follow these instructions when you've installed Mailcoach in an existing app.
The spatie/laravel-mailcoach-postmark-feedback package can handle bounce feedback coming from Postmark. All e-mail addresses that permanently bounce will be unsubscribed from all lists.
This package automatically adds the correct X-PM-Message-Stream header for Postmark Broadcast support. Make sure the name of your configuration set is available under the mailcoach.postmark_feedback.message_stream configuration key.
Here's an example for a configuration set that is named mailcoach:
// in config/mailcoach.php'postmark_feedback' => [
'message_stream' => 'newsletters',