It&#x27;s also good to point out that .NET Core (effectively a subset of the .NET Framework) and Roslyn (C# compiler) are open source on GitHub.<p>See: <a href="https:&#x2F;&#x2F;github.com&#x2F;dotnet" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;dotnet</a> and <a href="http:&#x2F;&#x2F;dotnet.github.io" rel="nofollow">http:&#x2F;&#x2F;dotnet.github.io</a><p>I&#x27;m a .NET team member at Microsoft.