smfx

@Marvino98 I use [this](https://github.com/Igosuki/binance-rs-async/blob/c3ab0e9d0bdb141b56108caadc7167531894873a/src/futures/userstream.rs#L35) method for keeping the connection alive. [Binance doc](https://binance-docs.github.io/apidocs/futures/en/#start-user-data-stream-user-stream) advices to ping it every 30 minutes.

[Link](https://binance-docs.github.io/apidocs/futures/en/#event-order-update) on docs.