bevyengine/bevy · error

Requested non-send data {} does not exist in the `World`.

Error message

Requested non-send data {} does not exist in the `World`.
                Did you forget to add it using `app.insert_non_send` / `app.init_non_send`?
                Non-send data can also be added by plugins.

What it means

Error "Requested non-send data {} does not exist in the `World`. Did you forget to add it using `app.insert_non_send` / `app.init_non_send`? Non-send data can also be added by plugins." thrown in bevyengine/bevy.

Source

Thrown at crates/bevy_ecs/src/world/deferred_world.rs:496

    pub fn get_resource_mut<R: Resource<Mutability = Mutable>>(&mut self) -> Option<Mut<'_, R>> {
        // SAFETY: &mut self ensure that there are no outstanding accesses to the resource
        unsafe { self.world.get_resource_mut() }
    }

    /// Gets a mutable reference to the non-send data of the given type, if it exists.
    ///
    /// # Panics
    ///
    /// Panics if the data does not exist.
    /// Use [`get_non_send_mut`](World::get_non_send_mut) instead if you want to handle this case.
    ///
    /// This function will panic if it isn't called from the same thread that the data was inserted from.
    #[inline]
    #[track_caller]
    pub fn non_send_mut<R: 'static>(&mut self) -> Mut<'_, R> {
        match self.get_non_send_mut() {
            Some(x) => x,
            None => panic!(
                "Requested non-send data {} does not exist in the `World`.
                Did you forget to add it using `app.insert_non_send` / `app.init_non_send`?
                Non-send data can also be added by plugins.",
                DebugName::type_name::<R>()
            ),
        }
    }

    /// Gets a mutable reference to non-send data of the given type, if it exists.
    /// Otherwise returns `None`.
    ///
    /// # Panics
    /// This function will panic if it isn't called from the same thread that the data was inserted from.
    #[inline]
    pub fn get_non_send_mut<R: 'static>(&mut self) -> Option<Mut<'_, R>> {
        // SAFETY: &mut self ensure that there are no outstanding accesses to the data
        unsafe { self.world.get_non_send_mut() }
    }

View on GitHub (pinned to 396ca72708)

Solutions

1. Add the non-send data via app.insert_non_send(...) / app.init_non_send::<R>()
2. Use get_non_send_mut() and handle the Option instead of panicking
3. Only access non-send data from the main thread

When it happens

Trigger: Thrown at crates/bevy_ecs/src/world/deferred_world.rs:496 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of bevyengine/bevy@396ca72708 (2026-08-20). Data as JSON: /api/errors/e4ec139d0d609884. Report an issue: GitHub.