.NET Compiler Platform ("Roslyn")

The .NET Compiler Platform ("Roslyn") provides open-source C# and Visual Basic compilers with rich code analysis APIs. You can build code analysis tools with the same APIs that Microsoft is using to implement Visual Studio!

End User Preview and SDK Preview

Try potential language and IDE features, and build code-aware C# and Visual Basic tools with the same API Microsoft uses.
NUGET     Install-Package Microsoft.CodeAnalysis -Pre


Get the Preview   

Open Source

We are now developing the C# and Visual Basic compilers in the open on CodePlex. Join us!
  git clone https://git01.codeplex.com/roslyn  


Join us on CodePlex   



Preview Features


Smarter Refactorings


Refactorings like Inline Rename build on the Compiler’s binding API to detect and resolve conflicts automatically. 

Smart conflict resolution lets you trust that refactorings won’t break your code.


Language Innovation


Try prototypes of potential language features, such as:

  • Primary constructors
    public class Point(int x, int y)
  • Declaration expressions
    s.TryParse(out var x)
  • Indexed members


Rich Code Analysis APIs


Build your own code analysis tools on top of the syntax, symbol, and binding APIs that Visual Studio uses, along with Workspaces APIs such as Find All References.