nautechsystems/nautilus_trader · error

Component {component_id} not found in actor registry

Error message

Component {component_id} not found in actor registry

What it means

Raised in `Trader::load_component_state` when the global actor registry has no component registered under `component_id` (cast to the requested type `T` via `try_get_actor_unchecked::<T>`). The trader cannot deliver persisted state to a component that is not registered, so state loading fails for it.

Source

Thrown at crates/system/src/trader.rs:1703

                    .get(strategy_id)
                    .copied()
                    .map(|callbacks| (*strategy_id, callbacks))
                    .ok_or_else(|| {
                        anyhow::anyhow!("Strategy {strategy_id} state callback not found")
                    })
            })
            .collect()
    }

    fn load_component_state<T>(
        component_id: Ustr,
        state: PersistedComponentState,
    ) -> anyhow::Result<()>
    where
        T: DataActor + DataActorNative + Debug + 'static,
    {
        let mut component = try_get_actor_unchecked::<T>(&component_id).ok_or_else(|| {
            anyhow::anyhow!("Component {component_id} not found in actor registry")
        })?;
        component.on_load(state)
    }

    fn save_component_state<T>(component_id: Ustr) -> anyhow::Result<PersistedComponentState>
    where
        T: DataActor + DataActorNative + Debug + 'static,
    {
        let component = try_get_actor_unchecked::<T>(&component_id).ok_or_else(|| {
            anyhow::anyhow!("Component {component_id} not found in actor registry")
        })?;
        component.on_save()
    }

    /// Initializes the trader, transitioning from `PreInitialized` to `Ready` state.
    ///
    /// This method must be called before starting the trader.
    ///

View on GitHub (pinned to 18893faf8b)

Solutions

1. Verify the component with that ID is added to the trader/system before state loading runs
2. Ensure the type parameter `T` matches the concrete registered type of the component
3. Check for ID renames or config changes between the state-saving run and the restoring run; map or migrate old IDs
4. Fix any initialization failure that prevented the component from registering, then retry restoration

// before restoring, confirm the component is registered
if !trader.is_registered(&component_id) {
    skip_or_register(component_id);
}

fn is_component_registered<T: DataActor>(trader: &Trader, id: &ComponentId) -> bool {
    trader.try_get_actor::<T>(id).is_some()
}

match trader.load_state() {
    Err(e) if e.to_string().contains("not found in actor registry") => {
        // reconcile saved component IDs with the current system config
    }
    other => other?,
}

When it happens

Trigger: Calling state restore with a `PersistedComponentState` whose `component_id` does not resolve to a registered actor of type `T` — the component was never added, was already disposed, or the requested type does not match the registered concrete type.

Common situations: Restoring a saved-state snapshot into a system configured with fewer/different components; renamed actor IDs between runs; custom persistence code calling the typed loader with the wrong `T`; restart after the component failed to initialize.

Understand the failure class

Background: "Not found" and "does not exist" errors: why "Task not found", "No such folder", and "Can't find" fire when a lookup comes back empty — this error's family across 14 libraries.

Related errors

• Active execution intent {intent_id} was not found
• Actor for {id} not found
• Actor type mismatch for '{id}': expected {expected_type:?},
• RPC block feed active without an RPC client
• Pool {pool_identifier} is not registered

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/aee125bbb318a086. Report an issue: GitHub.