> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cronozen.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Multi-Tenant Architecture

> How Cronozen isolates tenant data and manages center-based access

# Multi-Tenant Architecture

## Tenant Isolation Model

Cronozen uses **row-level tenant isolation** with Prisma scoped models. Every data query is automatically filtered by `center_id`.

```typescript theme={null}
// All queries scoped to current center
const scopedPrisma = createScopedPrisma(centerId);
const members = await scopedPrisma.centerMembership.findMany();
// → WHERE center_id = 'center_123' automatically applied
```

## Actor-Workspace Separation

| Actor          | Data Access                                                                                       |
| -------------- | ------------------------------------------------------------------------------------------------- |
| **Instructor** | Workspace and center data completely isolated. Must explicitly enter a center.                    |
| **Parent**     | Can view data across all centers where children are enrolled. Cross-center aggregation supported. |
| **Admin**      | Full access within their center scope.                                                            |

## Membership-Based Access

There is no direct center access. All access flows through memberships:

```
Actor → CenterMembership (ACTIVE) → Center Data
```

<Warning>
  The `getActor` center\_id fallback has been removed. All center access must go through `center_memberships`. This was verified with zero affected rows in staging and production.
</Warning>

## Scoped vs Base Prisma

| Mode           | Use Case                                               | Audit     |
| -------------- | ------------------------------------------------------ | --------- |
| `scopedPrisma` | Normal operations within current center                | Automatic |
| `basePrisma`   | Cross-center queries (parent aggregation, admin tools) | Required  |

```typescript theme={null}
// ✅ Normal: scoped to current center
const schedules = await scopedPrisma.schedule.findMany();

// ⚠️ Cross-center: explicitly audited
const allCenters = await basePrisma.center.findMany({
  where: { id: { in: authorizedCenterIds } }
});
```

## Center Scope Helpers

```typescript theme={null}
// Require center scope — throws if not in center context
const { centerId } = requireCenterScope(session);

// Get center scope or error
const result = getCenterScopeOrError(session);
```

## Tenant Types

| Type          | Description              |
| ------------- | ------------------------ |
| `CENTER`      | Standard center tenant   |
| `WORKSPACE`   | Personal actor workspace |
| `PROGRAM`     | Program within a center  |
| `WHITE_LABEL` | Partner-branded instance |