> ## 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.

# Build with Cronozen

> What you can build on the Cronozen platform

# Build with Cronozen

Cronozen is a vertical SaaS operating system. You don't build from scratch — you build **on top of** a platform that already handles multi-tenancy, authentication, billing, and audit trails.

***

## What You Get Out of the Box

<CardGroup cols={3}>
  <Card title="Multi-Tenant Isolation" icon="shield">
    Row-level data isolation, scoped database queries, center-based access control — ready from day one.
  </Card>

  <Card title="SSO & Auth" icon="key">
    Central authentication (auth.cronozen.com), JWT tokens, actor family linking, social login (Kakao, Apple, Google).
  </Card>

  <Card title="Decision Proof (DPU)" icon="link">
    SHA-256 hash chains for tamper-evident audit trails. Every decision is provable.
  </Card>

  <Card title="White-Label" icon="palette">
    Custom domains, branding, landing pages. Your customer sees their brand, not yours.
  </Card>

  <Card title="Billing" icon="credit-card">
    Toss Payments integration, subscription management, plan-based feature gating.
  </Card>

  <Card title="AI Automation" icon="robot">
    Workflow engine, pgvector embeddings, decision support with governance guardrails.
  </Card>
</CardGroup>

***

## Use Cases

### Rehabilitation & Therapy Platform

Build a center management system for rehabilitation facilities.

```
What you build:        Therapy scheduling, progress tracking, parent portal
What Cronozen handles: Multi-center isolation, therapist-patient matching,
                       DPU session proof, voucher billing, parent cross-center view
```

**Key APIs:** Centers, Schedules, DPU, Membership

**White-label example:** `slowpace.co.kr` — a branded rehab center platform running on Cronozen infrastructure.

***

### Education & Training LMS

Build HRD-Net compliant remote training or workshop management.

```
What you build:        Course content, assessment design, training programs
What Cronozen handles: HRD-Net compliance (heartbeat, EMON, FDS), QR attendance,
                       DPU proof, sequential learning gates, billing
```

**Key APIs:** LMS Learning, Assessment, Attendance, EMON

**Compliance:** 27+ HRD-Net regulatory requirements built in. EMON electronic monitoring integration included.

***

### Welfare Center Management

Build a welfare service management system for elderly care, disability support, or community services.

```
What you build:        Service programs, case management, reporting
What Cronozen handles: Multi-project settlement, compliance monitoring,
                       consent tracking, audit trails, schedule optimization
```

**Key APIs:** Centers, Schedules, DPU, Compliance

***

### Partner Platform (Franchise / White-Label)

Build a franchise management platform where you onboard and manage multiple centers.

```
What you build:        Partner dashboard, center analytics, custom branding
What Cronozen handles: Center provisioning, cross-center analytics,
                       revenue share tracking, white-label DNS/proxy, SSO
```

**Key APIs:** Partner, Provisioning, White-Label Config

***

### AI Governance Platform

Build compliance tooling for organizations using AI in regulated industries.

```
What you build:        Policy management, risk assessment UI, audit reports
What Cronozen handles: DPU hash chains, 5-level governance guards, evidence lifecycle,
                       JSON-LD export, chain verification, 6W responsibility extraction
```

**Key APIs:** DPU, Compliance, Audit

***

## Integration Patterns

### Pattern 1: White-Label SaaS

Deploy your own branded instance on a custom domain.

```
Your domain (brand.co.kr)
    ↓ CloudFlare Worker
Cronozen infrastructure
    ↓ Multi-tenant isolation
Your center's data only
```

**Setup time:** \~2 hours with the [White-Label Guide](/guides/white-label-setup)

***

### Pattern 2: Hub Integration

Connect your existing app to Cronozen via SSO and API.

```typescript theme={null}
// Your app authenticates via Cronozen SSO
const sso = await fetch('https://cronozen.com/api/auth/sso/token', {
  method: 'POST',
  headers: { Authorization: `Bearer ${opsToken}` },
  body: JSON.stringify({ targetApp: 'your-app' }),
});

// Your app calls Cronozen APIs for data
const schedules = await fetch('https://cronozen.com/api/schedules', {
  headers: { Authorization: `Bearer ${token}` },
});
```

***

### Pattern 3: DPU as a Service

Use Cronozen's DPU engine as a standalone audit trail for your existing application.

```python theme={null}
from cronozen import CronozenClient

client = CronozenClient(token="your-token")

# Record any decision from your app
dpu = client.create_dpu(
    content="Model v2.1 approved for production deployment",
    reference_type="ml-model-approval",
    reference_id="model_v2.1",
    tags=["ai-governance", "production"]
)

# Later: prove the decision was made and unaltered
verification = client.verify_dpu(dpu["id"])
assert verification["valid"] == True
```

***

## Getting Started

<CardGroup cols={2}>
  <Card title="Quickstart" icon="rocket" href="/getting-started/quickstart">
    First API call in 5 minutes
  </Card>

  <Card title="cURL Examples" icon="terminal" href="/examples/curl-quickstart">
    Copy-paste ready API examples
  </Card>

  <Card title="TypeScript SDK" icon="code" href="/examples/typescript-sdk">
    Full client library with types
  </Card>

  <Card title="OpenAPI Spec" icon="file-code" href="/openapi.yaml">
    Import into Postman, Insomnia, or AI tools
  </Card>
</CardGroup>