In 2026 expect a pipeline round on computing daily per-merchant settlement summaries from a high-volume UPI transaction stream with exactly-once guarantees, a SQL round on payment-health monitoring (merchants whose success rate drops below a threshold, conditional aggregation, partitioned by state), and a feature-engineering round on low-latency rolling per-user fraud signals. Because money is involved, interviewers weight idempotency, deduplication, and reconciliation against the ledger over generic ETL. Ground every answer in real UPI settlement and fraud-scoring workflows, and be precise about how you avoid double-counting.
About PhonePe
India's largest UPI app by volume; also offers insurance, mutual funds, gold, and merchant payments.
- Products
- PhonePe (UPI app) · PhonePe for Business · PhonePe Insurance · Pincode (e-commerce)
- Competitors
- Google Pay · Paytm · Amazon Pay · MobiKwik
- Scale
- Largest UPI app in India by transaction volume. Filed DRHP via SEBI confidential route. Reverse-flipped to India in 2022.
PhonePe recruitment process
01
Recruiter screen and technical pre-screen
02
SQL and data-manipulation round
03
Payment-stream pipeline and feature-engineering round
04
Hiring-manager and behavioural round, then offer
What to expect in each round
01
Round 1 (45-60 min)
SQL round on conditional aggregation and payment-health metrics.
02
Round 2 (60 min)
pipeline design round on exactly-once settlement aggregation.
03
Round 3 (45-60 min)
fraud feature-engineering round with rolling windows.
04
Round 4 (45 min)
behavioural and hiring-manager round.
Technical questions PhonePe asked
Sourced from 2+ candidate post-mortems. Hit Practice to answer any one with AI voice feedback.
- 01
Medium
On-call has gotten miserable, engineers paged 3-4 times/night, half false alarms. Walk me through the redesign you'd lead.
- 02
Hard
Given a stream of UPI transactions, find the top-K merchants by volume in the last 10 minutes with a sliding window. Walk me through your data structure choice.
- 03
Hard
Implement a rate limiter for an API that must allow 5000 requests per second per merchant. Which algorithm, and how does it behave at the boundary?
- 04
Medium
Find the number of ways to make a payment of amount N using given UPI cashback denominations. Then optimise the space complexity of your DP.
- 05
Hard
Design a pipeline that computes daily per-merchant settlement summaries from a high-volume UPI transaction stream. How do you guarantee no transaction is double-counted?
- 06
Medium
Write SQL to detect merchants whose daily transaction success rate dropped below 90% on any day in the last week, across all states.
- 07
Hard
How would you build a fraud-signal feature pipeline that computes rolling per-user aggregates (velocity, distinct devices) with low latency for scoring?