uBase is the evolution of the Umbraco /base framework, and is based on ASP.NET WebAPI.
The package lets you create REST api's running side-by-side with Umbraco and you can also protect your api's based on the currently logged on Member or backend User.
You can also protect by Member group and even Member Type or User Type!
All this can be specified for the entire service, or individual functions.
You can install it as a NuGet package or as a Umbraco Package. Right now they are one and the same, but in the future the Umbraco package will include some awesome built-in api's.
Please note that uBase lives in the "uBase" URI and is hit before Umbraco, so your services will hide any same-named Umbraco content pages.