Cosmos
Cosmos is an operating system "construction kit"
...Cosmos (C# Open Source Managed Operating System) is an operating system development kit that uses Visual Studio as its development environment. Despite C# in the name any .NET-based language can be used including VB.NET, Fortran, Delphi Prism, IronPython, F# and more. Cosmos itself and the kernel routines are primarily written in C#, and thus the Cosmos name. Cosmos is not an operating system in the traditional sense, but instead, it is an "Operating System Development Kit". Cosmos lets you create operating systems just as Visual Studio and C# normally let you create applications. ...