This is a Laravel notification channel package for sending push notifications via OneSignal. It integrates with Laravel's notification system to allow applications to send OneSignal notifications using Laravel's familiar notification syntax. The package provides a service provider, channel implementation, message builder with trait-based feature composition, and a payload factory for translating Laravel notification targeting to OneSignal parameters. It supports all major OneSignal features including targeting by player ID, email, tags, segments, external user IDs, buttons, web buttons, attachments, and silent notifications.