PostgreSQLPrismaNestJSMulti-tenancyAug 2025 · 7 min read
Building Multi-tenant SaaS with PostgreSQL & Prisma ORM
Patterns for schema isolation, row-level security, and connection pooling in high-concurrency Node.js environments.
Designing a multi-tenant database requires balancing strict data separation with operational simplicity. Row-level tenancy with tenantId scoping in Prisma middleware offers an elegant, scalable approach.
1. Automatic Tenant Scoping via Prisma Client Extensions
Prisma client extensions allow you to intercept all queries and automatically append where: { tenantId } based on the active AsyncLocalStorage context.
typescriptsnippet
export const extendedPrisma = (tenantId: string) =>
prisma.$extends({
query: {
$allModels: {
async findMany({ args, query }) {
args.where = { ...args.where, tenantId };
return query(args);
},
},
},
});