nautechsystems/nautilus_trader · error

Order {client_order_id} not found in cache

Error message

Order {client_order_id} not found in cache

What it means

Lookup failure inside the matching engine: an order referenced by client_order_id is no longer present in the cache (e.g. purged after closure or evicted), so the engine cannot continue processing for it.

Source

Thrown at crates/execution/src/matching_engine/mod.rs:5234

            self.remove_queue_position(order.client_order_id());

            // MarketToLimit reads `cached_filled_qty` in its caller to compute leaves;
            // its own cleanup happens there after the read.
            if order.order_type() != OrderType::MarketToLimit {
                self.purge_cached_filled_qty_if_closed(order.client_order_id());
            }
        }

        if self.config.support_contingent_orders
            && let Some(contingency_type) = order.contingency_type()
        {
            match contingency_type {
                ContingencyType::Oto => {
                    if let Some(linked_orders_ids) = order.linked_order_ids() {
                        for client_order_id in linked_orders_ids {
                            let mut child_order = match self.order_snapshot(*client_order_id) {
                                Some(child_order) => child_order,
                                None => anyhow::bail!("Order {client_order_id} not found in cache"),
                            };

                            if child_order.is_closed() || child_order.is_active_local() {
                                continue;
                            }

                            // Check if we need to index position id
                            if let (None, Some(position_id)) =
                                (child_order.position_id(), order.position_id())
                            {
                                self.cache
                                    .borrow_mut()
                                    .add_position_id(
                                        &position_id,
                                        &self.venue,
                                        client_order_id,
                                        &child_order.strategy_id(),
                                    )

View on GitHub (pinned to 18893faf8b)

Solutions

1. Verify the order was not already closed and purged from the cache
2. Re-add or re-query the order before retrying the operation that referenced it

When it happens

Trigger: Thrown at crates/execution/src/matching_engine/mod.rs:5234 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/1f5b7dae634f497a. Report an issue: GitHub.