Design Photo Storage with SHA-256 Content Deduplication and Safe Deletion
Company: OpenAI
Role: Software Engineer
Category: System Design
Difficulty: hard
Interview Round: Onsite
Overview: Design a photo storage service that deduplicates identical uploads by their SHA-256 content hash. Cover the upload flow with server-side verification, concurrent identical uploads, deletion with reference counting and garbage collection, and the privacy risks of deduplicating across users. It tests content-addressed storage design.