Multi-Tenant Laravel SaaS: Foundational Decisions Worth Making Early

The author presents a series aimed at helping Laravel developers avoid costly mistakes when building multi-tenant SaaS applications. They argue that key choices, such as where tenant data lives and how requests identify their company, are inexpensive to make at the start but expensive to change later. The author shares personal regret over treating the system as multi-tenant without multi-user support, which later forced a major rewrite. The series follows a fictional invoicing app where each tenant is a Company, and it focuses on design reasoning rather than packages or frameworks. It assumes a single Laravel application with a shared database and company_id columns, while deliberately excluding topics like per-tenant databases and single sign-on.