macOS 13 Stage Manager API for Developers

This article explores whether Apple provides a dedicated Stage Manager API in macOS 13 Ventura, explains how the feature interacts with third-party software, and outlines how developers can optimize their applications for this windowing environment.

Apple does not provide a public, dedicated Stage Manager API for developers in macOS 13. Developers cannot programmatically create Stage Manager sets, force applications into specific stages, or query the operational state of Stage Manager directly through a specialized framework.

Instead, Stage Manager functions entirely at the operating system and window server level. macOS automatically handles window grouping, transitions, and thumbnail generation in the sidebar without requiring explicit implementation from application developers. Standard AppKit and SwiftUI applications are compatible with Stage Manager by default.

Although there is no direct API, developers can influence how their applications behave within Stage Manager by utilizing standard NSWindow and AppKit lifecycle APIs:

  • Window Collection Behaviors: Setting NSWindow.CollectionBehavior determines how windows participate in spaces and Exposé, which directly impacts their visibility and behavior in Stage Manager groupings.
  • Window Levels and Styles: Utility panels (NSPanel), floating windows, and modal dialogs are treated differently by Stage Manager. Non-standard windows with levels such as .floating or .utility often remain visible across stage switches rather than receding into the sidebar with the primary application window.
  • State Restoration: Implementing NSWindowRestoration ensures that multi-window arrangements and document states reopen accurately when a user switches between stages or relaunches the application.

To deliver the best experience in Stage Manager, developers should focus on adhering to standard macOS window management paradigms, supporting native multi-window workflows, and properly configuring window roles rather than seeking a dedicated Stage Manager integration.