Stream processing is a critical tool in cybersecurity, allowing for immediate action on potential threats by processing data with minimal latency. DeltaStream exemplifies this capability by enabling the detection of suspicious user login activities through a streaming analytics pipeline. By leveraging a Kafka Store topic for failed login events, a continuous query identifies users attempting to access multiple accounts within a short timeframe, flagging them as suspicious. This rapid detection facilitates immediate follow-up actions such as account freezing and notification alerts. The system's SQL-based approach supports not only this simple use case but also more complex scenarios, highlighting DeltaStream's versatility in managing and securing streaming data.