nautechsystems/nautilus_trader · error · anyhow::Error

BitMEX only supports PRICE trailing offset type, was {offset

Error message

BitMEX only supports PRICE trailing offset type, was {offset_type:?}

What it means

submit_order rejects trailing stop orders whose TrailingOffsetType is anything but PRICE: BitMEX pegs the order with an absolute trailing-stop offset (TrailingStopPeg) and cannot express basis-point or tick offsets.

Source

Thrown at crates/adapters/bitmex/src/http/client.rs:1704

        if let Some(display_qty) = display_qty {
            params.display_qty(quantity_to_u32(&display_qty, &instrument));
        }

        if let Some(order_list_id) = order_list_id {
            params.cl_ord_link_id(order_list_id.as_str());
        }

        let is_trailing_stop = matches!(
            order_type,
            OrderType::TrailingStopMarket | OrderType::TrailingStopLimit
        );

        if is_trailing_stop && let Some(offset) = trailing_offset {
            if let Some(offset_type) = trailing_offset_type
                && offset_type != TrailingOffsetType::Price
            {
                anyhow::bail!(
                    "BitMEX only supports PRICE trailing offset type, was {offset_type:?}"
                );
            }

            params.peg_price_type(BitmexPegPriceType::TrailingStopPeg);

            // BitMEX requires negative offset for stop-sell orders
            let signed_offset = match order_side {
                OrderSide::Sell => -offset.abs(),
                OrderSide::Buy => offset.abs(),
            };
            params.peg_offset_value(signed_offset);
        }

        // Pegged orders (BBO) via params override
        if peg_price_type.is_none() && peg_offset_value.is_some() {
            anyhow::bail!("`peg_offset_value` requires `peg_price_type`");
        }

View on GitHub (pinned to 18893faf8b)

Solutions

1. Set TrailingOffsetType::Price on the trailing stop order
2. Configure the strategy/venue defaults to use PRICE offsets for BitMEX
3. Translate percent/tick offsets into price offsets before submitting

Example fix

// before
.trailing_offset_type(TrailingOffsetType::Percent)
// after
.trailing_offset_type(TrailingOffsetType::Price)

if order.trailing_offset_type().is_some_and(|t| t != TrailingOffsetType::Price) {
    return Err(anyhow::anyhow!("BitMEX trailing stops require TrailingOffsetType::Price"));
}

When it happens

Trigger: Calling submit_order with a trailing-stop order whose trailing_offset_type is Some(t) where t != TrailingOffsetType::Price.

Common situations: Reusing a strategy configured for another venue that defaults to percent or tick trailing offsets; constructing orders from config that names a different TrailingOffsetType.

Related errors

• BitMEX only supports PRICE trailing offset type, was {offset
• `peg_offset_value` requires `peg_price_type`
• Pegged orders only supported for LIMIT order type, was {orde
• `peg_offset_value` requires `peg_price_type`
• Pegged orders only supported for LIMIT order type, was {orde

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/498c221db9dd4d71. Report an issue: GitHub.