Talk: A .NET developer’s view of Windows 8 Metro style app development

I just came back from BUILD where I gave a talk about a new .NET profile that managed developers will be using when writing Windows 8 Metro style apps. You can watch the video at


Portable Library Tools Release

We just released the official version of the Portable Library Tools. The set of tools and updates to .net platform allow you to create dlls that can be used in .NET Framework, Silverlight, Windows Phone, and XBOX projects. You can download the tools here and read more about them on MSDN. 


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…


PDC 2008 Talk: Framework Design Guidelines

Our PDC talk has been posted on Channel9. Here is the talk summary: Learn about guidelines that have helped the Microsoft .NET Framework grow into the most popular developer framework Microsoft has ever created. After ten years of use, we have an enormous amount of real customer data about what makes great framework design….


Framework Design Guidelines Videos

Brad and I just did a couple of video interviews that are now accessible online. In the first one, we are talking about our PDC presentation (for those at the PDC, it’s at 4pm today). You can get it at 10 Years of Framework Design Guidelines (video). The second interview is about just released 2nd edition…


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. 


API Design Myth: Exceptions are for "Exceptional Errors"

I was updating FDG section on exceptions. I added one anntation that I thought I would post here as well:   KRZYSZTOF CWALINA One of the biggest misconceptions about exceptions is that they are for “exceptional conditions.” The reality is that they are for communicating error conditions. From a framework design perspective, there is no…