> ## Documentation Index
> Fetch the complete documentation index at: https://yn-c9bb3266.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Yuno Testing Gateway

> Built-in testing gateway to simulate payment outcomes without external provider credentials

## Overview

The Yuno Testing Gateway is a built-in simulated provider that allows you to test the full payment flow without configuring real provider credentials. It supports cards, PIX, bank transfers, and other payment methods in a controlled sandbox environment.

<Note>
  The Testing Gateway is available by default in all sandbox accounts. No additional configuration is required to start using it.
</Note>

## Supported Payment Methods

| Payment Method     | Testing Gateway Support | Simulated Behaviors                      |
| ------------------ | ----------------------- | ---------------------------------------- |
| Credit/Debit Cards | Yes                     | Approve, decline, 3DS, timeout           |
| PIX                | Yes                     | QR code generation, instant confirmation |
| Bank Transfer      | Yes                     | Redirect simulation, pending status      |
| OXXO               | Yes                     | Voucher generation                       |
| PSE                | Yes                     | Bank selection, redirect flow            |

## How It Works

<Steps>
  <Step title="Enable the Testing Gateway">
    Navigate to **Dashboard > Connections** in your sandbox environment. The Yuno Testing Gateway should appear as an available provider. If not enabled, toggle it on.
  </Step>

  <Step title="Set routing rules (optional)">
    By default, sandbox routes all transactions through the Testing Gateway. To test specific routing scenarios, configure rules in **Dashboard > Routing Rules**.
  </Step>

  <Step title="Send test transactions">
    Use [test cards](/guides/testing/test-cards) and the standard API flow. The Testing Gateway processes the transaction and returns simulated responses.

    ```javascript theme={"theme":{"light":"github-dark","dark":"github-dark"}}
    const payment = await fetch('https://api-sandbox.y.uno/v1/payments', {
      method: 'POST',
      headers: { /* sandbox auth headers */ },
      body: JSON.stringify({
        checkout_session: 'session-id',
        payment_method: { type: 'CARD', token: 'test-token' },
        amount: { currency: 'BRL', value: 50.00 },
        country: 'BR',
      }),
    });
    ```
  </Step>

  <Step title="Verify results">
    Check the payment status in the API response or in **Dashboard > Payments**. The Testing Gateway provides realistic response structures matching real provider formats.
  </Step>
</Steps>

## Simulating Specific Outcomes

The Testing Gateway determines the outcome based on the test card number used:

| Test Card          | Simulated Outcome             |
| ------------------ | ----------------------------- |
| `4111111111111111` | Approved                      |
| `4000000000000002` | Declined (generic)            |
| `4000000000009995` | Declined (insufficient funds) |
| `4000000000003220` | 3DS challenge required        |

For non-card methods (PIX, bank transfer), the Testing Gateway always returns a successful pending status with simulated payment details (QR codes, redirect URLs).

## Testing Webhooks

The Testing Gateway triggers webhook events just like a real provider:

| Event               | When Triggered                      |
| ------------------- | ----------------------------------- |
| `payment.created`   | Payment submitted                   |
| `payment.succeeded` | Payment approved                    |
| `payment.failed`    | Payment declined                    |
| `payment.pending`   | Async payment awaiting confirmation |
| `refund.succeeded`  | Refund processed                    |

<Warning>
  Some webhook event types may return 404 in sandbox. This is a known sandbox limitation. See [Webhook Setup](/guides/webhooks/setup) for details.
</Warning>

## Limitations

* The Testing Gateway is only available in sandbox environments
* Response times are instant (does not simulate real provider latency)
* Settlement and reconciliation flows are not simulated
* Provider-specific error codes are generic simulations

## Transitioning to Real Providers

When moving to production:

1. Configure real provider credentials in **Dashboard > Connections**
2. Update routing rules to point to production providers
3. Switch API keys and base URL to production
4. The Testing Gateway is not available in production