backend-multi-tenancy

Backend Multi-Tenancy

Purpose

Implement tenant isolation in a SaaS application using row-level, schema-per-tenant, or DB-per-tenant strategies with automated provisioning and safe migrations. The core challenge is guaranteeing that no tenant can access another tenant's data while balancing operational complexity, cost, and compliance requirements.

Architecture/Decision Trees

Isolation Strategy Decision Tree

Is regulatory compliance required (GDPR/SOC 2/HIPAA)?
  |-- YES --> Do tenants require full data separation?
  |     |-- YES --> DB-per-tenant (highest isolation)
  |     |-- NO  --> Schema-per-tenant
  |-- NO --> Expected tenant count?
        |-- < 100, B2B --> Schema-per-tenant
        |-- >= 100, B2C --> Row-level (shared database)
        |-- Mixed (B2B+B2C) --> Hybrid: row-level for B2C, schema for B2B

Hybrid Strategy Matrix

Tier	Isolation	Database	Provisioning	Backup
Free	Row-level	Shared	Auto (self)	Global
Pro	Schema	Shared	Auto (self)	Global
Enterprise	DB	Dedicated	Manual	Per-tenant

Agent Protocol

Trigger

Exact user phrases: "multi-tenancy", "SaaS", "tenant isolation", "row-level security", "DB per tenant", "schema per tenant", "tenant provisioning", "tenant migration", "multi-tenant database", "tenant context".

Input Context

• Number of tenants (current and projected).
• Regulatory requirements (GDPR, SOC 2, HIPAA).
• Database technology and hosting model.
• Existing authentication/user system.
• Pricing tiers and tenant size distribution.
• Team operational capacity for managing per-tenant infrastructure.

Output Artifact

Tenant isolation configuration or implementation plan. No file unless requested.

Response Format

Strategy: {Row-level|Schema-per-tenant|DB-per-tenant}
Isolation Level: {shared|semi-isolated|fully-isolated}
Provisioning: {automated|manual}
Migration: {shared schema|per-tenant}