The Official Swiftmailer Transport for Postmark.
Updating to the newer version of Guzzle to resolve versioning conflicts in packages that depend upon this package, and Guzzle.
Based on feedback from users, we are splitting the Laravel Adapter into a separate package. If you're using this package with Laravel 5+, you'll want to install that package, instead:
composer require wildbit/laravel-postmark-provider
There are effectively no code changes with this modification, but it will organize the packages in a more idiomatic and appropriate way.