How to Add Multi-Tenant File Storage to Your Next.js project in 10 Minutes.

Introduction If you have worked on Saas projects before, there's a good chance you've already hit this wall. Your users need to upload files. So you spin up a storage bucket from your favorite storage provider like AWS S3, Cloudflare R2 etc, wire up some SDK code, and ship it. But then the questions start piling up: How do you track how much storage each user is consuming? How do you enforce storage limits per user without building a whole quota system from scratch? How do you make sure User A can never access User B's files? Most developers answer these questions by inventing a folder naming convention like user_123/uploads/avatar.jpg and then build manual tracking on top. It works. But it takes a week to do properly, and it has nothing to do with your actual product. Here's what that week actually looks like: You spin up one big shared bucket for example from S3 or R2. Every file from every user lands in the same place. So you invent a prefix naming scheme and pray your logic never h