multi-tenant-saas-backend

To prevent cross-tenant data exposure in a multi-tenant SaaS backend, use a three-client database pattern that separates anonymous, user-scoped JWT, and service-role admin queries. This avoids accidental RLS bypass and ensures strict tenant isolation.

Implementing row level security policies involves applying enforceable templates for owner-only access, public read with owner write, and org-scoped membership checks. Correct auth.uid casting is required to consistently enforce these rules across tables.

The best way to verify payment webhooks and prevent replay attacks is to verify signatures against the raw request body and enforce replay protection via event deduplication. This idempotent approach ensures duplicate webhook deliveries do not trigger repeated actions.

To handle credit billing for streamed AI outputs without inconsistent charges, use deduct-before-call credit logic with an automatic refund-on-failure mechanism. This atomic credit deduction logs usage and auto-refunds when streamed responses fail to produce usable output.

You need a separate service-role admin client for your multi-tenant database to reduce privilege mistakes and avoid accidental RLS bypass. Admin actions are gated by environment-variable allowlists and auditable mutations to maintain security boundaries.