Pastebin

Store text snippets and serve them by ID. It looks like the URL shortener, but the payload is 20× bigger, so the real design question is where the bytes live: metadata in a database, content in an object store, hot pastes in a cache.

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Duration 45:00

Requirements checklist

Create a paste (text up to 10 MB, typically ~10 KB) and get back an unguessable ID.Read a paste by ID; optional syntax highlighting and raw view.Pastes can expire (10 minutes to never) or be burn-after-read.Signed-in users can list and delete their pastes.Reads p99 under 200 ms for typical pastes.99.9% availability for reads; a paste, once acknowledged, is never lost.Storage cost dominates, so cold content must sit in cheap storage.

Clarifying questions

What are the typical and maximum paste sizes?
Are pastes public, unlisted or private? Do IDs need to be unguessable?
What expiry options exist, and is burn-after-read required?
How long must pastes be kept if they never expire?

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requirements

Suggested time: about 6 minutes. Also covers burn-after-read semantics, privacy of IDs and deletion.

Notes for requirements