While the Windows 10 Redstone 4 (Spring Update) release has been delayed, Microsoft is mostly done with that preview branch (aside from fixing bugs). Now the company is full-on development for Redstone 5, which will launch officially this fall. We are starting to hear about prospective features, but the release could bring a major shift to Windows 10 as a whole.

Indeed, the company is reported to be introducing a new Windows SKU which will be called Windows 10 Lean. As the name suggests, this would be a lighter stripped down version of the platform. It would be lean because Microsoft will remove programs that are unnecessary for the running of the OS.

The Lean version of Windows was discovered by Twitter user @tfwboredom, who spotted Windows 10 Lean as an installer in the preview build 17650. That’s a Redstone 5 preview currently in the Skip Ahead branch of the Windows Insider Program.

Pointing to its stripped-down nature, the Windows 10 Lean x64 clean install is 2GB lighter than Windows 10 Pro. Microsoft will remove unneeded packages from the platform, but will also take some customization options. For example, there will be no wallpaper by default on the OS.

Registry Editor is also removed, although core packages like this can be imported. The one questions surrounding this subject is what exactly is Windows 10 Lean?

New SKU?

It seems to be a completely fresh SKU, but there is a debate that perhaps it is part of the existing Windows 10 S. You may remember Microsoft launched Windows 10 S last year as an individual SKU. Since then, the company folded Windows 10 S into a “Mode” which ships with Windows 10 Pro.

It (S Mode) is essentially a lighter version of Windows, so how will Lean differentiate? Well, it seems it will be completely stripped down to bare bones, which Windows 10 S is not. Microsoft has been long-rumored to be working on a stripped-down version of the OS.