itsual Multi-Tenancy Design
Overview
Multi-tenancy improves efficiency but introduces isolation, noisy-neighbor, and data-leakage risks that must be designed for explicitly.
When to Use
- Building SaaS or multi-customer platforms
- Deciding between pooled, siloed, or hybrid tenancy models
- Reviewing tenant isolation
Key Decisions
- Tenancy model (database per tenant, shared DB with tenant_id, hybrid)
- Data isolation and encryption requirements
- Noisy neighbor protection (rate limits, resource quotas)
- Tenant-specific configuration and feature flags
- Onboarding, offboarding, and data deletion (including GDPR-style requirements)
Principles
- Isolation is a security and compliance property, not just an implementation detail
- Make tenant context explicit in every relevant operation
- Design for the operational realities of many tenants
Verification
- Cross-tenant data access is prevented and tested
- Resource isolation or quotas exist where needed
- Tenant lifecycle operations are well-defined