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name: storage description: File storage - uploads, CDN, blobs. Use when handling files.

Storage Guideline

Tech Stack

• Storage: Vercel Blob
• Framework: Next.js (with Turbopack)
• Platform: Vercel

Non-Negotiables

• All file uploads must be validated (type, size, content)
• Signed URLs for private content access
• No user-uploaded content served from main domain (XSS prevention)
• File deletion must cascade with parent entity deletion

Context

File storage is deceptively complex. Users expect uploads to just work, but there are many ways for it to fail — large files, slow connections, wrong formats, malicious content.

Vercel Blob is the SSOT for file storage. No custom implementations.

Driving Questions

• What happens when an upload fails halfway?
• How are large files handled without blocking?
• What file types are allowed and how is it enforced?
• How long are files retained after entity deletion?
• What's the storage cost and is it sustainable?