Cω attempts to make datastores (such as databases and XML documents) accessible with the same ease and type safety as traditional types like strings and arrays. Many of these ideas were inherited from an earlier incubation project within the WebData XML team called X# and Xen. Cω also includes new constructs to support concurrent programming; these features were largely derived from the earlier Polyphonic C# project.
Available now as a compiler preview, Cω's features have been used in the creation of the LINQ extensions in C#. The concurrency constructs have also been released in a slightly modified form as a library, named Joins Concurrency Library, for C# and other .NET languages by Microsoft Research.