Drop-in Multi-Tenancy for Node.js

Tenant hierarchy

1. d0AcmeSecroot tenant
2. d1NorthStar MSPchild tenant

max_users: 1000inherited from d0

NorthStar MSP sets no value for max_users, so it resolves the value from its parent. The quick example builds this tree.

Install

# Direct library (no HTTP overhead)
npm install @stratum-hq/lib pg

# Or use the SDK with Express/Fastify middleware
npm install @stratum-hq/sdk

Quick example

import { Pool } from "pg";
import { Stratum } from "@stratum-hq/lib";

const pool = new Pool({ connectionString: process.env.DATABASE_URL });
const stratum = new Stratum({ pool });

// Create a root tenant
const root = await stratum.createTenant({
  name: "AcmeSec",
  slug: "acmesec",
  isolation_strategy: "SHARED_RLS",
});

// Create a child tenant
const msp = await stratum.createTenant({
  name: "NorthStar MSP",
  slug: "northstar_msp",
  parent_id: root.id,
});

// Config with inheritance
await stratum.setConfig(root.id, "max_users", { value: 1000, locked: false });
const config = await stratum.resolveConfig(msp.id);
// { max_users: { value: 1000, inherited: true, source_tenant_id: root.id } }

What Stratum includes

• Tenant hierarchies. Model tenants as a tree using PostgreSQL ltree. Parent-child relationships with efficient subtree queries, ancestor resolution, and cycle-safe moves.
• Config inheritance. Config values flow root-to-leaf. Children inherit parent values unless they override. Parents can lock keys to prevent any descendant from changing them. Sensitive values are encrypted with AES-256-GCM.
• Permission delegation. Three delegation modes: LOCKED (immutable), INHERITED (overridable), and DELEGATED (re-delegatable). Revocation controls blast radius with CASCADE, SOFT, or PERMANENT semantics.
• Three isolation strategies. Choose per-tenant: Shared RLS (row-level security), Schema-per-Tenant (logical separation), or Database-per-Tenant (maximum isolation). Mix strategies within the same hierarchy.
• Two integration paths. Embed @stratum-hq/lib directly for zero-HTTP-overhead performance, or run the control plane as a service and use @stratum-hq/sdk with Express/Fastify middleware.
• Built-in compliance. GDPR data export (Article 20), hard-purge (Article 17), consent tracking with purpose and expiration, audit logging with before/after state, and multi-region data residency.

Packages

Start here

For the direct library, install @stratum-hq/lib and pg. @stratum-hq/core comes with @stratum-hq/lib as a dependency.

Package	Description
@stratum-hq/lib	Direct library: embed in Node.js with no HTTP
@stratum-hq/core	Shared types, Zod schemas, error classes, constants. Installed with @stratum-hq/lib

Add as needed

Package	Description
@stratum-hq/sdk	HTTP client, LRU cache, Express/Fastify middleware
@stratum-hq/db-adapters	PostgreSQL adapters: raw pg, Prisma, Sequelize, Drizzle
@stratum-hq/mongodb	MongoDB tenant isolation: shared collection, collection-per-tenant, database-per-tenant
@stratum-hq/mysql	MySQL tenant isolation: shared table, table-per-tenant, database-per-tenant + TypeORM, Knex, Sequelize
@stratum-hq/nestjs	NestJS integration: guard, @Tenant() decorator, DI module
@stratum-hq/hono	Hono middleware: tenant extraction, ALS context
@stratum-hq/test-utils	Cross-tenant isolation test helpers
@stratum-hq/compliance	Compliance kernel: coverage scoring, finding state machine, control types
@stratum-hq/create	Project scaffolding: npx @stratum-hq/create my-app
@stratum-hq/cli	Project init, DB migration, framework scaffolding
@stratum-hq/react	React provider, tenant tree, config/permission editors