Since Anniversary Update (Windows 10 1607) Xbox One has supported UWP developers and the Windows Store has supported UWP apps targeting Xbox One. You can use any Xbox One as a developer machine. This blog will walk you through the process of setting it up. It's a lot of steps, but pretty easy.
First, what are the prerequisites?
- An Xbox One with local, shared network access
- Visual Studio 15 Preview 5 (or VS 2015 Update 3+)