A customer asks you to delete their data. It is in thirty systems including backups and a warehouse. Design the erasure.

Erasure is a distributed transaction across systems that were never designed to participate in one, and backups make a literal delete impossible. The design that works is a deletion ledger plus crypto-shredding, not a fan-out of delete statements.

Updated Sep 2026 · Grounded in researched DevOps, SRE and platform engineering interview loops, written to a senior-engineer editorial bar, and never padded to hit a word count.