As a .NET developer, you should avoid using the newly released Managed Extensibility Framework as its license prevents its use beyond the Windows platform. This will prevent your .NET software from running on Linux or MacOS in the future.

Luckily, there is a cross platform solution available today that has no platform limitations: Mono.Addins, a technology inspired by Eclipse's own plugin system. We have tutorials, reference manuals, API docs, our FAQ our public groups and multiple large applications with source code available that you can learn from (MonoDevelop, Banshee, F-Spot and Gnome-Do).

The rule obviously applies to any new APIs that are built for .NET as they are not immediately available for Mono. But unlike the binary-only APIs, these half-open source code releases pose additional problems for the open source CLI:

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