AuthHub - Multi-Tenant Authentication System

A complete authentication and organization management system for Supabase projects. Use this skill when implementing:

• User signup/signin
• Organization (tenant) creation
• Multi-tenant data isolation
• Team invitations
• Role-based access control (RBAC)
• Organization switching
• Permission management

Explicit Triggers

• authhub
• authentication setup
• multi-tenant
• org switching
• team invitations
• RBAC
• tenant management

Quick Start

1. Database Schema: See DATABASE_SCHEMA.md - Run migrations first
2. Supabase Config: See SUPABASE_CONFIG.md - Configure auth settings
3. API Templates: See API_TEMPLATES.md - Copy and customize
4. Frontend Setup: See FRONTEND_SETUP.md - React context and hooks
5. Checklist: See IMPLEMENTATION_CHECKLIST.md - Track progress

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Deployment Modes

AuthHub supports two deployment modes. Choose based on your use case:

Mode 1: Standalone App (Most Common)

Use this if: Building a single SaaS product with its own Supabase project.

┌─────────────────────────────────────────────────────────┐
│                  Your Supabase Project                   │
├─────────────────────────────────────────────────────────┤
│  AuthHub Tables (public schema)                         │
│  ├── products (your single product entry)               │
│  ├── user_profiles                                      │
│  ├── tenants (organizations)                            │
│  ├── user_tenants                                       │
│  ├── roles (for your product)                           │
│  └── user_role_assignments                              │
├─────────────────────────────────────────────────────────┤
│  Product Tables (public schema with RLS)                │
│  ├── customers (has organization_id + RLS)              │
│  ├── orders (has organization_id + RLS)                 │
│  └── ... all your product tables                        │
└─────────────────────────────────────────────────────────┘

Characteristics:

• Single Supabase project per product
• Still uses products table (for future central AuthHub integration)
• Product tables in public schema with organization_id column
• RLS policies filter data by organization
• Queries include product_id filter (your single product)

Mode 2: Multi-Product Platform

Use this if: Multiple products share the same Supabase database (like DataSwim + Onboard).

┌─────────────────────────────────────────────────────────┐
│               Shared Supabase Project                    │
├─────────────────────────────────────────────────────────┤
│  AuthHub Tables (public schema)                         │
│  ├── products (DataSwim, Onboard, etc.)                 │
│  ├── user_profiles                                      │
│  ├── tenants                                            │
│  ├── user_tenants                                       │
│  ├── roles (per product)                                │
│  └── user_role_assignments (includes product_id)        │
├─────────────────────────────────────────────────────────┤
│  Product A Tables    │    Product B Tables              │
│  (public or schema)  │    (public or schema)            │
└─────────────────────────────────────────────────────────┘

Characteristics:

• Single Supabase project shared by multiple products
• Each product has unique product_id
• All queries MUST filter by product_id
• Enables cross-product features and central management

Future: Central AuthHub Dashboard

By keeping the products table in all deployments, we enable future capabilities:

• Central dashboard to view all products across the ecosystem
• API integration to sync product/user data
• Cross-product analytics and management
• Single sign-on across products (future feature)

---

Data Isolation Strategies

Strategy 1: RLS with organization_id (RECOMMENDED)

Best for: Most SaaS applications with fixed schemas.

Every product table includes organization_id and RLS policies:

-- Example: customers table
CREATE TABLE public.customers (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  organization_id UUID NOT NULL REFERENCES public.tenants(id),
  name TEXT NOT NULL,
  email TEXT,
  created_at TIMESTAMPTZ DEFAULT NOW()
);

-- RLS Policy
ALTER TABLE public.customers ENABLE ROW LEVEL SECURITY;

CREATE POLICY "Users can view their org's customers"
ON public.customers FOR SELECT
USING (
  organization_id IN (
    SELECT tenant_id FROM public.user_tenants
    WHERE user_id = auth.uid() AND is_active = true
  )
);

Pros:

• Simple to implement
• Standard PostgreSQL pattern
• Easy to query across organizations (for admin dashboards)
• Works with Supabase's built-in RLS

Cons:

• All tenants share table structure
• Large tables may need additional indexing

Strategy 2: Schema-per-tenant (Advanced)

Best for: Applications where tenants define their own data structures (like DataSwim).

Each organization gets its own PostgreSQL schema:

-- Creates: tenant_abc123def456...
SELECT create_tenant_schema('abc123-def4-5678-...');

Pros:

• Complete data isolation
• Tenants can have different table structures
• Easier to export/delete tenant data

Cons:

• More complex to manage
• Can't easily query across tenants
• Schema migrations must run per-tenant

When to use Schema-per-tenant:

• Users create their own database tables (like DataSwim)
• Regulatory requirements demand physical data isolation
• Per-tenant backup/restore requirements

---

Architecture Overview

┌─────────────────────────────────────────────────────────┐
│                    Supabase Auth                         │
│              (auth.users - managed by Supabase)          │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│                   public.user_profiles                   │
│         (extended user info, links to auth.users)        │
└─────────────────────────────────────────────────────────┘
                            │
              ┌─────────────┴─────────────┐
              ▼                           ▼
┌─────────────────────┐     ┌─────────────────────────────┐
│  public.user_tenants │     │ public.user_role_assignments │
│  (user ↔ org link)   │     │ (user ↔ org ↔ product ↔ role)│
└─────────────────────┘     └─────────────────────────────┘
              │                           │
              └─────────────┬─────────────┘
                            ▼
┌─────────────────────────────────────────────────────────┐
│                    public.tenants                        │
│                    (organizations)                       │
└─────────────────────────────────────────────────────────┘
                            │
                            ▼
┌─────────────────────────────────────────────────────────┐
│            Product Tables (with organization_id)         │
│     customers, orders, projects, etc. + RLS policies     │
└─────────────────────────────────────────────────────────┘

Key Concepts

1. Product-Scoped Roles

Each product has its own roles tied to a product_id. Even in standalone mode, keep this structure for future compatibility.

2. Junction Tables

NEVER query tenants directly for user access. Always go through:

• user_tenants - for user-org membership
• user_role_assignments - for roles (always filter by product_id)

3. Soft Deletes

All tables use is_active boolean. Never hard delete - set is_active = false.

4. Organization ID in Product Tables

Every product table should have organization_id column with appropriate RLS policies.

5. Always Filter by Product ID

Even in standalone apps, include product_id in queries. This ensures:

• Consistent patterns across all AuthHub implementations
• Future compatibility with central management
• Clean separation if you add another product later

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Tech Stack Assumptions

This skill assumes:

• Framework: Next.js 14/15 with App Router
• Language: TypeScript
• Database: Supabase (PostgreSQL)
• Auth: Supabase Auth
• Deployment: Netlify, Vercel, or similar

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Files in This Skill

File	Purpose
DATABASE_SCHEMA.md	Complete SQL migrations
SUPABASE_CONFIG.md	Supabase dashboard settings
API_TEMPLATES.md	Next.js API route templates
FRONTEND_SETUP.md	React context and components
IMPLEMENTATION_CHECKLIST.md	Step-by-step checklist