framework:
    messenger:
        routing:
            # route all messages that extend this example base class or interface
            'App\Message\AbstractAsyncMessage': async
            'App\Message\AsyncMessageInterface': async

            'My\Message\ToBeSentToTwoSenders': [async, audit]
===

===
framework:
    messenger:
        routing:
            # route all messages that extend this example base class or interface
            'App\Message\AbstractAsyncMessage': async
            'App\Message\AsyncMessageInterface': async

            'My\Message\ToBeSentToTwoSenders': [async, audit]