Originally published at hafiz.dev Every SaaS app eventually hits the same question: how do you make one application serve multiple customers with separate data? If you're building with Filament, the answer is closer than you think. Filament ships with a built-in tenancy system that handles tenant switching, automatic resource scoping, registration, and profile management out of the box. But here's the thing: the docs cover what's available without walking you through the full implementation. You get a list of methods and interfaces, and then you're on your own to wire them together. If you've read the Building a SaaS with Filament guide, you have the foundation. This post picks up where that left off: adding proper multi-tenancy so your users can belong to teams, switch between them, and see only their team's data. We'll build the full system: tenant model, user relationships, panel configuration, registration, profile editing, automatic scoping, and the security gotchas that trip up most developers.…