During its Developer Day event today, Microsoft announced a new installer format for packaging apps called MSIX. It's essentially a brand new type of container, and what's neat about this one is that it supports all types of Windows applications, including Universal Windows Program (UWP) apps and classic Win32 programs.
MSIX could conceivably get Win32 programs into the Windows Store without having them become UWP apps, and hopefully points at a long-needed rework of the Windows Store to make it, well, less terrible. We don't know just yet if that's a route Microsoft is going to take. All we really know at this early stage is that it will be supported in the Microsoft Store.
Another key thing we don't know yet: how MSIX will compare to UWP, and whether it solves the many criticisms we (and Tim Sweeney) have had of the Universal Windows Platform. On the bright side, there's some transparency with MSIX: Microsoft is making the new container open source. There's already an SDK available on Github for developers to mess around with. In the description, Microsoft notes that MSIX enables developers on a variety of platforms to pack and unpack packages to be distributed from either the Microsoft Store or their own custom content distribution networks.
Bye 25 types of installers, the future is MSIX (on all platforms) and open source: https://t.co/PKTqXQRBxF #WindowsDevDayMarch 7, 2018
The transition to MSIX won't happen overnight, even assuming we see widespread adoption. The new container could pave the way for a nice reduction in the number of installers and containers on Windows. We'll follow up with more on MSIX as we learn more.