Managing multiple platforms in Visual Studio

Who has not struggled to correctly manage multiple platform configurations in Visual Studio without ending to edit a solution file or tweak some msbuild files by hand? Recently, I decided to cleanup the antique SharpDX.sln in SharpDX that was starting to be a bit fat and not easy to manage. The build is not extremely bizarre there, but as it needs to cover the combinations of NetPlatform x OSPlatform x DirectXVersion x Debug/Release with around 40 projects (without the samples), it is an interesting case of study. It turns out that modifying the solution to make a clean multi-platform build was impossible without hacking msbuild in order to circumvent unfortunate designs found in Microsoft msbuild files (and later to found at work in Xamarin build files as well). In this post, we will go through the gotchas found, and we will see also why Visual Studio should really improve the configuration manager if they want to improve our developers experience.