Welcome to the MEF Community Site

Important: this site hosts source code for unsupported, pre-release versions of MEF. If you want to use MEF in production, you should strongly consider using the supported versions included in the .NET Framework and Silverlight.

What is it?

The Managed Extensibility Framework (MEF) is a composition layer for .NET that improves the flexibility, maintainability and testability of large applications. MEF can be used for third-party plugin extensibility, or it can bring the benefits of a loosely-coupled plugin-like architecture to regular applications.

Status

MEF is a part of the Microsoft .NET Framework, with types primarily under the System.ComponentModel.Composition.* namespaces.

• MEF has shipped with .NET 4.0 and Silverlight 4
• MEF 2 is under development
  • New features are available in the .NET Framework 4.5 Beta
  • Preview source and binaries for .NET 4 are available on this site
  • Integration of MEF with ASP.NET MVC can be installed from NuGet

Documentation

• Reference documentation for released versions of MEF is available on MSDN
• For an introduction to MEF see the Hands-On Lab
• Upcoming features are discussed on the BCL team blog