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## v1.0.9

Added OAuth2 client-credentials support. Pass `clientId`/`clientSecret` instead of `apiKey` and the SDK handles the token exchange and refresh automatically:

```php
$client = new PayabliClient(
    clientId: "...",
    clientSecret: "...",
    options: ['baseUrl' => Environments::Sandbox->value]
);
```

The existing `apiKey`-based constructor still works unchanged — no action needed if you're not switching auth methods. See the [PHP SDK guide](/developers/platform-sdk-php-guide) and [Authentication](/developers/authentication) to compare both methods.