How to Build Multi-Tenant SaaS with SvelteKit

Step 1: Project Setup

npx sv create my-saas-app
cd my-saas-app
npm install
npm run dev

Step 2: Database Schema

// organizations, users, memberships tables (Drizzle, SQLite — as in the starter kit)
import { integer, sqliteTable, text, uniqueIndex } from 'drizzle-orm/sqlite-core';

export const organizations = sqliteTable('organizations', {
  id: text('id').primaryKey(),
  name: text('name').notNull(),
  slug: text('slug').notNull(),
  createdAtMs: integer('created_at_ms').notNull()
}, (t) => [uniqueIndex('organizations_slug_uq').on(t.slug)]);

export const memberships = sqliteTable('memberships', {
  id: text('id').primaryKey(),
  orgId: text('org_id').references(() => organizations.id),
  userId: text('user_id').references(() => users.id),
  role: text('role').notNull(), // 'owner' | 'admin' | 'member'
  createdAtMs: integer('created_at_ms').notNull()
});

Step 3: Authentication

Implement session-based authentication with HTTP-only cookies.

Step 4: Multi-Tenancy

Resolve tenant from subdomain or cookie and enforce in all queries.

Step 5: Role-Based Access Control

Implement owner/admin/member roles with server-side enforcement.

Skip the Line

The Multi-Tenant SvelteKit Starter includes all of this with 77 tests, so you can start with a production-ready SaaS in hours, not weeks.