Phonepe Software Engineer interview: DSA and order-feed design

After a recruiter-style touchpoint, the process became technical quickly. I had a machine-coding round on a hackathon platform with a live panel and several candidates on the call. The interviewer gave the problem, I worked alone in a tight window of about 90 minutes in one phase, and I sent my working solution to the recruiter in a zip file.

Soon afterward, an interviewer reviewed my work in a roughly 30-minute discussion about my implementation and reasoning. The DSA round had two hard problems: Sliding Window Maximum and Burst Balloons. I could not find the optimal approach for Sliding Window Maximum and landed nearer O(n log n), while I was able to solve Burst Balloons, so I still passed that round.

The final stage was system design for an order feed in a food-ordering app. It needed real-time updates tied to a global orderId, strict publish and client-polling latency, search and filtering by orderId, restaurantId, status, and time window, plus downloadable historical order summaries under a relaxed SLA. I did not receive an offer, but the questions made clear that implementation depth and performance thinking mattered.

Location: India. Overall feedback: positive. Offer status: no offer.