Project Description

 This project is Reactive Extensions for Ruby and is actively developed by Microsoft Open Technologies, Inc., in collaboration with a community of open source developers.

A brief intro

The Reactive Extensions (Rx) is a library for composing asynchronous and event-based programs using observable sequences and LINQ-style query operators. Using Rx, developers represent asynchronous data streams with Observables query asynchronous data streams using LINQ operators , and parameterize the concurrency in the asynchronous data streams using Schedulers . Simply put, Rx = Observables + LINQ + Schedulers.

Whether you are authoring a traditional desktop or web-based application, you have to deal with asynchronous and event-based programming from time to time. Desktop applications have I/O operations and computationally expensive tasks that might take a long time to complete and potentially block other active threads. Furthermore, handling exceptions, cancellation, and synchronization is difficult and error-prone.

Using Rx, you can represent multiple asynchronous data streams (that come from diverse sources, e.g., stock quote, tweets, computer events, web service requests, etc., and subscribe to the event stream using the IObserver<T> interface. The IObservable<T> interface notifies the subscribed IObserver<T> interface whenever an event occurs.

Because observable sequences are data streams, you can query them using standard LINQ query operators implemented by the Observable extension methods. Thus you can filter, project, aggregate, compose and perform time-based operations on multiple events easily by using these standard LINQ operators. In addition, there are a number of other reactive stream specific operators that allow powerful queries to be written.  Cancellation, exceptions, and synchronization are also handled gracefully by using the extension methods provided by Rx.

Rx complements and interoperates smoothly with both synchronous data streams (IEnumerable<T>) and single-value asynchronous computations (Task<T>) as the following diagram shows:


Single return value

Multiple return values







 Additional documentation, video, tutorials and HOL are available on MSDN.

What is included

The project includes the following libraries:

  • Reactive Extensions:
    • Rx.rb: The Reactive Extensions (Rx) for Ruby is a library for composing asynchronous and event-based programs using observable sequences and LINQ-style query operators.



There are lots of ways to contribute to the project, and we appreciate our contributors.

You can contribute by reviewing and sending feedback on code checkins, suggesting and trying out new features as they are implemented, submit bugs and help us verify fixes as they are checked in, as well as submit code fixes or code contributions of your own. Note that all code submissions will be rigorously reviewed and tested by the Rx Team, and only those that meet an extremely high bar for both quality and design/roadmap appropriateness will be merged into the source.

You will need to submit a Contributor License Agreement form before submitting your pull request. This needs to only be done once for any Microsoft Open Technologies OSS project. Download the Contributor License Agreement (CLA). Please fill in, sign, scan and email it to msopentech-cla at microsoft .com  (please prefix the email subject with RX– ).

Last edited Sep 9, 2013 at 6:23 PM by MSOpenTech, version 4