Design a Pastebin Service: Requirements, Entities, APIs and End-to-End Architecture

Build a text-sharing service similar to Pastebin. A client uploads a plain text document and receives a short URL. Anyone with that URL can open it and read the document. Work top-down: state functional and non-functional requirements, define the core entities, design the public API, and present a complete end-to-end architecture. The design should address short-key generation, separation of content from metadata, caching, expiration, and failure handling. Before designing,…