An early build of Polaris, a canceled SKU of Windows Core OS, has leaked online. The building is from the beginning of 2018, and contains nothing but just the core OS, which means that there is no composer (shell) or apps present. Windows Core OS is a modern version of Windows that runs HoloLens 2 and the upcoming Windows 10X, and has been in operation for many years.
We have covered Windows Core OS much earlier, but for those who are not interested, the Windows Core OS project aims to create a modular, universal Windows OS that provides older features and components for the benefit of modern user experiences. As a result, the operating system is more secure and efficient on low-end hardware, with better battery life and faster OS updates.
Because Windows Core OS has been in operation for so long, the project has gone through many different phases internally. Originally, Windows Core OS was to drive the Surface Duo with the Andromeda SKU, as well as laptops and tablets with the Polaris SKU. Polaris was actually Windows Core OS built specifically for PCs.
Polaris was canceled just around Andromeda was canceled, as both SKUs were replaced by Windows 1
The building that has leaked is the RS3 RTM building, but as mentioned above, the actual leak contains very little for tinker to mess with. It has no composer, which means there is no GUI, and there do not appear to be any apps in the box either. This leak serves two purposes: confirms the existence of Polaris for those who doubted it, and allows enthusiasts to fiddle with an old version of Windows Core OS.
Interestingly, the leak is also in the ARM32 architecture, which means that it can only start on older ARM32-based PCs such as the Surface RT. Once again, Polaris is a canceled version of Windows Core OS and will never ship, so do not expect to see this on PCs in the future. Windows 10X is the future of Windows Core OS on PCs, and will begin shipping on devices later this spring.
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