The Ledger and the Live Wire

A hard Pipeline Design interview practice problem on DataDriven. Write and execute real pipeline design code with instant grading.

Domain

Pipeline Design

Difficulty

hard

Seniority

mid

Problem

We run an online retail marketplace that emits about 2 billion order and refund events a day across 300 million listings. Seller-facing inventory and sales dashboards have to reflect a purchase within seconds, while finance needs an exactly-once daily profit-per-product number that stays correct even when refunds land days after the original order. Data science also wants the full raw event history retained for model training.

Practice This Problem

Solve this Pipeline Design problem with real code execution. DataDriven runs your solution and grades it automatically.