Visual Studio Add-Ins are small application extensions developed to improve the user experience from the IDE. I have been always curious how it is possible to create an external tool which has the ability to cooperate with Visual Studio's environment. I believed the extensions are often full of hacky and non-standard solutions. Development of an Add-in was surely far from my confort zone, so I've decided to take a deep dive to this area. The number of the Visual Studio Add-In articles on the web is not really astonishing, that's why I think you will find this article useful.