The various Skybrud.Social packages are build using .NET Framework 4.5, which is therefore the minimum required version of the .NET framework for Skybrud.Social to work.
As Skybrud.Social currently has a dependency for
System.Web, Client Profile and portable versions of the .NET framework are not supported.
There is also currently no support for .NET core. My plan is to add support for .NET core at some point, but so far I don't really have a plan for this. I haven't started any work on this yet.