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## v3.0.7

Added OAuth2 client-credentials support. Pass `client_id`/`client_secret` instead of `api_key` and the SDK handles the token exchange and refresh automatically:

```ruby
client = Payabli::Client.new(
    client_id: "...",
    client_secret: "...",
    base_url: Payabli::Environment::SANDBOX
)
```

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