Microsoft has announced the open sourcing of its Reactive Extensions (Rx). Rx is a model and framework for development which lets developers “glue together asynchronous data streams”, a particularly useful capability when many modern applications are built around bringing together data from sources as diverse as tweets, stock quotes, REST requests or event buses. The libraries are used by GitHub (in their GitHub for Windows application) and Netflix clients. GitHub’s Paul Betts notes that the developers at the company found the Rx proposition useful enough to create ReactiveCocoa, a Mac OS X port of the Rx-based ReactiveUI.