PayPal Software Engineer interview experience

As I talked through the architecture, I leaned into an event-driven approach. I explained publishing messages to Kafka and processing them through Flink, and I also discussed how I’d handle idempotency so duplicate events wouldn’t create incorrect results.

The rest of the conversation followed from that design—how the pieces would interact and what the system would need to reliably deliver notifications. What stood out was how concrete the prompt was and how much of the evaluation depended on whether my reasoning around event flow and correctness made sense.

By the time the round ended, I’d