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Code RoomGlobal payments data residency
HardPrep Room Coding #3160

Global payments data residency

System designDistributed systemsSenior–Staff~50 min

Design the sharding and data-placement strategy for a global payments platform that must satisfy data-residency law: a user's transaction data must physically reside in their home jurisdiction (EU data in EU, India data in India, etc.), while still supporting cross-border payments (an EU user pays an India merchant) and global fraud analytics. ~500M users, 30k tx/sec peak, strong consistency required within a single payment. Describe the partition key and placement policy, how routing works, how cross-border transactions stay consistent, and the central trade-off.

What a strong answer looks like

Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.

Clarify5:30 left
Estimate5:30 planned
Design16:30 planned
Deep dive13:30 planned
Failure9:00 planned
0:00
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