http://developers.de/blogs/damir_dobric/archive/2015/09/08/type-system-reference-in-dotnetcore.aspxTo compile a single program in dotnetcore , we obviously have to reference some assemblies, which implement at least the type system. Because the dotnetcore is build as set of nuget packages, it is required to explicitly (at least for now) reference allenCommunityServer 2008 SP1 (Build: 30619.63)