Design an audit log for a regulated bank: every admin action recorded, and nobody, including your own team, can quietly rewrite it.

Never-delete is a policy, not a control. Auditors and attackers both want to know what stops an admin with broad credentials, and the answer has to be mechanical.

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.