nautechsystems/nautilus_trader · error · anyhow::Error

Invalid config type for BinanceExecutionClientFactory. Expec

Error message

Invalid config type for BinanceExecutionClientFactory. Expected BinanceExecutionClientConfig, was {config:?}

What it means

The Binance execution client factory received a runtime config object whose concrete type is not BinanceExecutionClientConfig. It downcasts the generic config to the expected type via downcast_ref and fails with this message when the downcast returns None, so a Binance execution client can never be constructed from a mismatched config.

Source

Thrown at crates/adapters/binance/src/factories.rs:155

impl Default for BinanceExecutionClientFactory {
    fn default() -> Self {
        Self::new()
    }
}

impl ExecutionClientFactory for BinanceExecutionClientFactory {
    fn create(
        &self,
        trader_id: TraderId,
        name: &str,
        config: &dyn ClientConfig,
        cache: CacheView,
    ) -> anyhow::Result<Box<dyn ExecutionClient>> {
        let binance_config = config
            .as_any()
            .downcast_ref::<BinanceExecutionClientConfig>()
            .ok_or_else(|| {
                anyhow::anyhow!(
                    "Invalid config type for BinanceExecutionClientFactory. Expected BinanceExecutionClientConfig, was {config:?}",
                )
            })?
            .clone();

        let product_type = binance_config.product_type;

        binance_config.validate()?;

        match product_type {
            BinanceProductType::Spot => {
                // Spot uses cash account type and hedging OMS
                let account_type = AccountType::Cash;
                let oms_type = OmsType::Hedging;

                let core = ExecutionClientCore::new(
                    trader_id,
                    ClientId::from(name),

View on GitHub (pinned to 18893faf8b)

Solutions

Pass a BinanceExecutionClientConfig instance for the execution client factory registration
Check that the venue/config key you registered maps to the exec factory, not the data factory
Re-serialize/deserialize configs with the correct concrete type and keep adapter versions in sync
Log {config:?} in the message output to identify which type was actually supplied

Example fix

// before
config: BinanceDataClientConfig { .. } // registered for exec factory
// after
let exec_config = BinanceExecutionClientConfig {
    api_key,
    api_secret,
    product_type: BinanceProductType::UsdTFuture,
    ..Default::default()
};
factory.create(exec_config, cache).await

Defensive patterns

Strategy: type-guard

Validate before calling

fn is_binance_exec_config(cfg: &dyn ClientConfig) -> bool {
    cfg.as_any().downcast_ref::<BinanceExecutionClientConfig>().is_some()
}

Type guard

fn as_binance_exec_config(cfg: &dyn ClientConfig) -> Option<&BinanceExecutionClientConfig> {
    cfg.as_any().downcast_ref::<BinanceExecutionClientConfig>()
}

Try / catch

match factory.create(config.clone(), cache).await {
    Ok(client) => client,
    Err(e) if e.to_string().contains("Invalid config type") => {
        return Err(anyhow!("wrong config type for exec factory: {}", e));
    }
    Err(e) => return Err(e),
}

Prevention

Keep data-client and exec-client configs in separate, clearly named config structs
Assert the concrete config type in unit tests before wiring factories
Log config type names at startup to catch mismatches early

When it happens

Trigger: Calling create() on BinanceExecutionClientFactory with a config that is a different client's config struct (e.g. BinanceDataClientConfig, BinanceFuturesExecutionClientConfig-style type, or a generic ClientConfig) passed in the config registry for the BINANCE_EXEC venue.

Common situations: Config typed for the Binance data client but registered for the exec client; mixing adapter versions where the exec config type was renamed; passing a deserialized generic config map instead of the concrete typed struct.

Related errors

AI-assisted analysis of nautechsystems/nautilus_trader@18893faf8b (2026-09-08). Data as JSON: /api/errors/d7e88181bef6f2a9. Report an issue: GitHub.