MEF Primitives Explained

Daniel just wrote a really nice post explaining the basics of MEF primitives. I recommend this to all interested in the internals or in extending MEF.  


Custom Programming Models for MEF (Provider Model Contrib)

The MEF composition engine operates on (composes) abstractions called ComposableParts. By default, parts are implemented as simple .NET classes annotated with MEF attributes (ExportAttribute and ImportAttribute). But, we envision that some parts will be implemented through variety of different mechanisms. For example, parts can be .NET types annotated with external files, DLR objects, XAML files,…


MEF Preview #4 Released

We have just released a new update to MEF. I am super excited about this release as it represents something quite close to what we are going to ship in terms of public APIs. In the last milestone, we have done quite significant API cleanup, renamed many core types to what I think will be…


MEF on CodePlex

  We have just released an update to MEF. You can get it at The changes are quite significant: 1.       The preview ships with sources under a very permissive license (Ms-LPL). 2.       We now support constructor injection. Feature that the community asked for. 3.       We completely redesigned MEF’s extensibility points. The extensibility points are…


Extensible Framework Design Studio Released

This summer we had a high school intern, Nick Moloney, who worked on incorporating MEF into FDS. The fruits of his labor are now on code gallery. You can download the extensible FDS here. Congratulations to Nick! The current release has just a few extensibility points, but you should expect more in the future. 


POCO Support for MEF

Jason, our technical evangelist, just posted a sample showing how MEF can compose plain old CLR objects.


MEF and System.AddIns

Several people asked about the relationship between MEF and the technology in System.AddIn namespace. The answer is that these two are independent and complementary features. MEF is a primarily a composition engine. System.AddIn is an add-in activation and isolation technology. MEF’s engine will be able to compose objects that are simple CLR object, COM and…


MEF CTP 1 Released

Several members of my team have already spilled the beans, but yes (!) we just released our first public preview of MEF. You can grab the bits from here and read a past post for a high level overview. I am super excited about the release. It’s a very early preview and still lots of…


Managed Extensibility Framework

Several months ago we formed what we call Application Framework Core team. The charter of the team is to play the same role in the application frameworks space (WinForms, ASP.NET, WPF, Silverlight) as the Base Class Libraries (BCL) team plays at the bottom of the platform stack. The BCL team did a good job fulfilling…