Real-Time Transaction Streaming

You work as a data engineer at a global financial services company. The current pipeline ingests millions of daily credit card transactions via nightly batch jobs. The business now requires real-time processing and analysis for each transaction to support instant fraud detection and real-time reporting.

How would you redesign the ingestion and processing architecture to enable reliable, scalable, and consistent real-time streaming of transaction data?

Draft a design proposal outlining your approach.