File Storage (Cloud)
Cloud services like S3 or Supabase Storage that store and serve user-uploaded files such as images, documents, and media.
Cloud file storage separates your uploaded files from your application server. Instead of saving images to your server's disk (which gets wiped on redeployment), you upload them to a storage service that keeps them permanently and serves them via a URL.
Amazon S3 is the original and most popular option. Supabase Storage, Cloudflare R2, and Vercel Blob are newer alternatives with simpler APIs. Most work the same way: upload a file, get back a public or signed URL, store that URL in your database.
For vibe coders, file storage comes up whenever users need to upload profile pictures, documents, or media. AI can generate the upload handler, but you need to make the architectural decision of which storage service to use, whether files should be public or private, and how to handle size limits and file type validation.