Sunday afternoon, everything seemed very calm. The market was lukewarm, chat groups were lively, and our automated trading program was running as usual—fetching data, placing small orders, writing logs. Suddenly, a trade record flashed on the trading interface, coming from our account, but we hadn’t made any operation. Although the amount was small, that feeling was like hearing unfamiliar footsteps at night at home—immediately tense up all over.

A few people immediately exploded. Some thought the API key had been leaked, others suspected a problem with the exchange system. After a heated discussion, no conclusion was reached. Just as the argument was ongoing, a newcomer quietly asked: "We've been using this set of keys for over a month, why haven't we changed them?"

Instantly, everyone fell silent.

In the world of digital asset trading, we often regard API keys as the keys to the door—if kept hidden, we think they are foolproof. But in reality, simply hiding them is far from enough. Especially when using mainstream trading interfaces, sessions are actually temporary credentials with a limited validity period, like a valid pass that confirms your bot has permission to trade. If this credential is set to last too long, once stolen or leaked, the consequences are hard to imagine. That inexplicable trade was like a warning signal; we were lucky this time, with only minor losses. But next time? Relying on luck is a gamble we can't afford.

Since that day, I decided to eliminate this hidden danger completely. At first, I didn’t understand why it was necessary, then I got a bit angry, and finally I took matters into my own hands to improve the system. Since traders can take shifts, why can't the permissions in the code be refreshed in rotation? Our team decided to add an automatic session rotation mechanism into the system—simply put, to regularly update the interface credentials, each time with a new temporary pass, so even if hackers get the old one, it’s useless.