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An observable microservice bus .NET library that wraps the underlying transport in simple Rx based interfaces.
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Obvs: an observable microservice bus

observable services, obviously

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  • Obvs is just a library, not a framework - use as much or as little as you need.
  • Leverage messaging and Reactive Extensions to quickly compose a system of decoupled microservices.
  • Add new services and message contracts with a minimal amount of code and effort.
  • Don't tie yourself to any one transport, migrate between transports with minimal code changes required
  • Use a mix of transports and serialization formats, allowing you to pick what works for your services.
  • Declare a new Obvs ServiceBus easily using the fluent code based configuration.
  • Don't want to use Obvs message contract interfaces? Use the generic ServiceBus and supply your own.
  • Standardize on messaging semantics throughout by wrapping integrations with external API's as custom endpoints.
  • Don't distribute if you don't need to, Obvs ServiceBus includes a local in-memory bus.
  • Use one of the many available serialization extensions, or even write your own.
  • Easily debug and monitor your application using logging and performance counter extensions.


  • V5 - Next version, System.Reactive 4.1, supports netstandard2.0 and net46
  • V4 - Current version, System.Reactive 3.1.1, supports netstandard1.6 and net452

More Details

  • Convention based messaging over topics/queues/streams per service.
  • Multiplexing of multiple message types over single topics/queues/streams.
  • Dynamic creation of deserializers per type, auto-discovery of message contracts.
  • Exceptions are caught and raised on an asynchronous error channel.


  • Transports: ActiveMQ / RabbitMQ / NetMQ / AzureServiceBus / Kafka / EventStore
  • Serialization: XML / JSON.Net / NetJson / ProtoBuf / MsgPack
  • Logging: NLog / log4net
  • Monitoring: Performance Counters / ElasticSearch
  • Integrations: Slack


Define a root message type to identify messages as belonging to your service:

public interface IMyServiceMessage : IMessage { }

Create command/event/request/response message types:

public class MyCommand : IMyServiceMessage, ICommand { }

public class MyEvent : IMyServiceMessage, IEvent { }

public class MyRequest: IMyServiceMessage, IRequest { }

public class MyResponse : IMyServiceMessage, IResponse { }

Create your service bus:

IServiceBus serviceBus = ServiceBus.Configure()

Send commands:

serviceBus.Commands.Subscribe(c => Console.WriteLine("Received a command!"));
await serviceBus.SendAsync(new MyCommand());

Publish events:

serviceBus.Events.Subscribe(e => Console.WriteLine("Received an event!"));
await serviceBus.PublishAsync(new MyEvent());


	  .Subscribe(request => serviceBus.ReplyAsync(request, new MyResponse()));

serviceBus.GetResponses(new MyRequest())
	  .Subscribe(r => Console.WriteLine("Received a response!"), err => Console.WriteLine("Oh no!"));

Define custom endpoints that can wrap API calls or integrations with other systems:

public class MyCustomEndpoint : IServiceEndpointClient
    	Type _serviceType = typeof(IMyCustomServiceMessage);

    	public IObservable<IEvent> Events
            		// subscribe to external MQ broker

    	public Task SendAsync(ICommand command)
        		// call external API

    	public IObservable<IResponse> GetResponses(IRequest request)
        		// call external API and wrap response in observable

    	public bool CanHandle(IMessage message)
        		return _serviceType.IsInstanceOfType(message);

IServiceBus serviceBus = ServiceBus.Configure()
  .WithEndpoints(new MyCustomEndpoint())
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