A Clean Number for Every Merchant
A hard Pipeline Design mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.
- Domain
- Pipeline Design
- Difficulty
- hard
- Seniority
- L7
Interview Prompt
Our payments platform generates a daily log containing every transaction across all merchants. The finance and BI teams need a clean merchant-level summary - total volume, transaction count, average amount - but the raw logs have duplicates, schema inconsistencies, and no restart safety. Design a batch pipeline that reliably produces this summary.
Summary
Raw payment logs in. Clean merchant summaries out.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Draw your pipeline on the design canvas: sources, transforms, storage and checks
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision