Can we have a common assembly just for extension points

[fahad ash]

Can we have a common assembly Just for extension points. It would have nothing but interfaces attributed as TypeExtensionPoint.

And all other assemblies would reference that common assembly in order to Register extensions to those points. Can the main app also register extensions to those points? Should that common assembly be an Addin or Root?

I figured instead of giving extension developers the exe file to reference in their extensions, they should just reference one common dll and register extensions.

That common dll sure will have a public Extension Manager class that will give back extensions to whoever need them.