Can Filament handle multi-tenant SaaS?

Yes. Filament v3 has first class multi-tenancy through its Panel Builder. Each panel can be scoped to a tenant, and Filament integrates cleanly with Stancl tenancy and similar multi-tenant packages. We have shipped Filament SaaS admin panels serving thousands of tenants on a single architecture with proper isolation per tenant. The Panel Builder also lets you separate your customer facing panel from your internal back office panel using the same Filament codebase. More on our SaaS development page.