This is an example of a convention-based consumer with no dependencies on MassTransit.

FreeConsumer.cs

public class FreeConsumer
{
    public event EventHandler<MyPublishedEvent> MyPublish;
    
    public void CommandHandler(MyCommand command)
    {
        // process the command
        
        // the event handler will be bound by MT to publish the event handler message type
        MyPublish(this, new MyPublishedEvent(...));
    }
    
    // Request is a message type being consumed, Response is a message type being sent back
    public Response RequestHandler(Request request)
    {
        // process the request
        
        // will be sent via context.Respond to the requester
        return new Response(...);
    }
    
    // all thrown exceptions are returned as Fault<T>
}