Engineering · June 12, 2026 · 6 min read
Building a multi-tenant SaaS core
How a single tenant-scoped data layer keeps customers isolated by construction.
Multi-tenancy is the foundation of a platform that serves many customers from one codebase. The goal is simple to state and hard to guarantee: one tenant can never see another’s data.
We enforce isolation at the data layer, not by convention. Every tenant-owned record carries a tenant identifier, and a base query layer refuses to run without a tenant context — so a forgotten filter fails loudly instead of leaking silently.
That single decision compounds: every feature we build inherits isolation for free, and our tests assert it on every endpoint.