Video applications often generate numerous notifications, which can be overwhelming for users. To address this issue, Knock provides notification infrastructure that helps developers implement user-friendly notifications without building their own in-house system. By using Mux and Knock together, video app creators can build scalable, thoughtful, and battle-tested notifications. Knock's features include a standardized templating system, drag-and-drop workflow builder, code-level abstractions, custom components, and deep observability. With Knock, developers can create advanced notification workflows, real-time video notification feeds, and handle video subscriber notifications using webhooks.