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Code RoomGDPR deletion lineage tracking
HardPrep Room Coding #3316

GDPR deletion lineage tracking

System designDistributed systemsSenior–Staff~45 min

Under GDPR/CCPA, when a user requests deletion you must erase their personal data everywhere it propagated — but their PII has flowed from the source app DB through dozens of ETL jobs into warehouse tables, ML feature stores, derived aggregates, search indexes, caches, and analytics exports. Design a system that tracks where each user's PII lands and can fulfill a 'delete me' request completely and provably within the legal window, without breaking downstream tables that legitimately need aggregates. ~100M users, hundreds of datasets.

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.

Clarify5:00 left
Estimate5:00 planned
Design15:00 planned
Deep dive12:00 planned
Failure8:00 planned
0:00
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.