I specialize in multi-tenant SaaS architecture—building applications that serve multiple organizations from a single codebase while keeping data isolated, secure, and performant. Whether you're launching a B2B product or scaling an existing one, I design and implement tenant-aware backends that grow with your business.
Multi-Tenant Architecture Explained
Multi-tenancy means one application serves many customers (tenants) with logical data separation. I use PostgreSQL Row-Level Security (RLS) to enforce tenant isolation at the database level, ensuring that queries automatically filter by tenant ID. This approach is more secure and maintainable than application-level checks alone. RLS policies run at the database layer, so even if application code has a bug, tenants cannot access each other's data. I design tenant models that scale from dozens to thousands of organizations. The architecture supports white-labeling, tenant-specific configurations, and usage-based billing.
Technical Approach
I build multi-tenant systems with FastAPI or Django, PostgreSQL, and Redis. Tenant context is passed via JWT claims, API keys, or subdomain routing. I implement RLS policies, connection pooling per tenant when needed, and schema strategies (shared schema with tenant_id vs schema-per-tenant) based on your scale and compliance needs. For most B2B SaaS, a shared schema with a tenant_id column is the right choice—it's simpler to maintain and query. For strict isolation or compliance requirements, schema-per-tenant or database-per-tenant can be used. I set up middleware that injects tenant context into every request and ensures it's never forgotten.
Use Cases
Typical projects include: project management tools, CRM systems, HR platforms, billing and invoicing software, and industry-specific SaaS. I've built tenant onboarding flows, usage-based billing integration (Stripe), and admin dashboards for tenant management. Each tenant gets their own workspace, users, and data—all from one codebase. I've built SaaS for agencies managing multiple clients, platforms connecting buyers and sellers, and internal tools used by hundreds of teams. The key is designing for tenant isolation from the start.
Challenges I Solve
Clients often struggle with: migrating from single-tenant to multi-tenant, performance at scale, compliance (GDPR, SOC2), and tenant-specific customizations. I address these with clear architecture decisions, documentation, and incremental migrations that don't disrupt existing users. Migrating to multi-tenant is a significant undertaking—I plan it in phases, add tenant context gradually, and ensure data integrity throughout. For performance, I optimize queries, add indexes, and use caching where appropriate. Compliance requirements often need audit logs, data export, and deletion—I build these into the architecture.
Frequently Asked Questions
What is PostgreSQL Row-Level Security (RLS)?
RLS is a PostgreSQL feature that restricts which rows a user can see or modify. In multi-tenant apps, we set policies so each tenant only accesses their own data. It adds a security layer at the database level, reducing the risk of tenant data leakage.
Do you support schema-per-tenant vs shared schema?
Yes. Shared schema with a tenant_id column is common and easier to maintain. Schema-per-tenant is useful for strict isolation or when tenants need custom tables. I recommend the best approach based on your requirements.
Can you migrate an existing app to multi-tenant?
Yes. I've migrated single-tenant applications to multi-tenant architectures. It involves adding tenant context, RLS policies, and data migration. I plan the migration to minimize downtime and risk.