Despite numerous leaks (which have appeared on this blog and elsewhere) about Windows Core OS, a k a WCOS, Microsoft never has publicly explained this terminology. In part, this may be the result of the constantly evolving nature of WCOS. And based on a new report out today, it looks like there may be yet another new WCOS wrinkle.
WCOS is, in a nutshell, is the successor to Windows OneCore -- Microsoft's strategy to modularize Windows and create a shared kernel and dev platform that would enable the foundation of Windows 10 to be shared across devices, based on what I've heard from my sources.
Like Windows Central and others, I've been hearing that Microsoft was working to modularize Windows 10 further and create WCOS and a bunch of different shells (like Aruba, Sydney, Scarlett, Polaris, Andromeda and others) to work on different form factors. This was the plan of record up until earlier this year.
WCOS, however, lived on as the operating system for future Windows devices.
According to my contacts, however, a priority for WCOS shifted: Instead of being a Universal Windows Platform (UWP) only platform, as it was originally designed, Microsoft officials decided to allow WCOS to run Win32 apps.
The reason for this possible name/branding change makes sense to me. A number of customers who have purchased the very few PCs that shipped with Windows 10 in S Mode on by default have been confused by this variant. Windows 10 in S Mode looks like Windows and seems to run Windows apps. But it hasn't been all that clear that S Mode only lets users run a subset (UWP/Store) apps only and not all Win32 apps.
Microsoft hasn't completely axed Windows 10 in S Mode -- it's still available for customers who want its purported extra security and performance -- but it would be tough to characterize S Mode as a success (regardless of the telemetry methods used), I'd feel safe saying.
The biggest question I still have about WCOS is how it will work under the covers. Will it work like Microsoft's "Continuum" experience, in that plugging a WCOS device into a larger screen and keyboard will give users a full desktop-type experience? Will it use virtualization in some way, so that all WCOS applications run in a virtual machine hosted remotely? Will WCOS restrict applications so that Win32 apps run in a VM? I've heard from my sources that all of these ideas have been on the table at various points. I'm not sure which, if any, of these options has emerged as the "final" choice.
While I believe any brand-new Surface device types will run WCOS inside, I don't know which ones will run WCOS Lite. Some are speculating that whatever succeeds Andromeda might be a candidate for WCOS Lite. I haven't heard from any of my sources which devices Microsoft believes would be suited for such an OS.
Because of the still relatively small number of quality UWP/Store applications -- something that MSIX and Progressive Web Apps might help change at some point -- it's hard to see any new device shipping in the near-term being a potentially successful WCOS Lite platform.
Microsoft isn't commenting on Windows Lite or WCOS Lite. This post is just me taking info from sources and trying to connect the dots....
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