AppExit event not being received in bevy 0.16

[cswinter]

Bevy version

0.16.1

My bevy app has a system running in PostUpdate which listens to AppExit events to run code before the app exits. This was working as expected with bevy 0.15, but after upgrading to bevy 0.16, the system no longer seems to receive any AppExit events.

[cswinter]

It does seem to work when exiting with CTRL+C but not when closing the window.

[cswinter]

When closing the window, I see these logs but the AppExit event does not seem to trigger:

2025-07-02T01:32:33.017301Z  INFO system{name="bevy_window::system::exit_on_all_closed"}: bevy_window::system: No windows are open, exiting
2025-07-02T01:32:33.018295Z  INFO system{name="bevy_winit::system::despawn_windows"}: bevy_winit::system: Closing window 0v1

[grind086]

This sounds like a system ordering issue. exit_on_all_closed also runs during PostUpdate, so it may be running after your cleanup systems. You'll need to explicitly order them after exit_on_all_closed, or they may not see the AppExit.

You could also try moving the cleanup systems to the Last schedule if there are no conflicts there.

[cswinter]

Moving it to Last schedule worked, ty!

[occuros]

On macOS, it seems the event isn’t received when the application is exited using cmd + q. When closing it through the red x on the window, the event is captured. (Tried in multiple schedules including Last).

Ideally shouldn't this event be changed to an observer?