Users upload photos and videos from phones on unreliable networks. Design the path from camera roll to CDN.

The app server that proxies uploads through itself is the design that fails this question. Direct-to-storage, validate after arrival, and make CDN invalidation almost never necessary.

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.

The app server that proxies uploads through itself is the design that fails this question. Direct-to-storage, validate after arrival, and make CDN invalidation almost never necessary.

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