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Develop Your Own Operating System in C# or VB.NET CosmosOS/Cosmos Wiki GitHub

Cosmos (C# Open Source Managed Operating System) is an operating system development kit which uses Visual Studio as its development environment. Despite C# in the name any .NET Core based language can be used including VB.NET, F# and more. Cosmos itself and the kernel routines are primarily written in C#, and thus the Cosmos name. Besides that, NOSMOS (.NET Open Source Managed Operating System) sounds stupid.