Microsoft first announced Project Reunion at its Build 2020
developer conference and it could be the company’s best attempt
to improve the native app experience on Windows 10 by
bridging the gap between the two main app development
platforms – UWP and Win32.
Ever since the release of Windows 8 and Metro UI, Microsoft has
been trying to modernize Windows and its development platform.
Microsoft has also tried to convince developers to move to a
modern platform and support the Windows Store.
Project Reunion is expected to ‘reunite’ these two app
platforms, so developers will be able to easily write apps with
all the newest Windows 10 features and touch/modern API
What is Project Reunion?
Project Reunion isn’t a new app model and it doesn’t offer a
different set of APIs. Instead, it’s supposed to improve the
current development experience.
The world of Win32 and UWP are very different. For example,
both platforms offer different tools, which makes choosing one
platform over the other a decision that developers are more or
less stuck in.
For example, if a developer started working on a UWP app and
realized it cannot meet their needs, they had to abandon the
app. Likewise, if Win32 has been working for developers, there
is very little incentive to move to UWP. This is where Project
Reunion comes in.
Microsoft wants to close the divide between Win32 and UWP
Ignite 2021, Microsoft explained that Project Reunion is
about bringing the two worlds (UWP and Win32) together so that
the divide doesn’t exist.
With Project Reunion, Microsoft is decoupling Win32 and UWP
APIs from Windows 10, and taking the APIs that shipped in UWP
and making them available to Win32 to “bridge” the gap between
the two platforms.
“We chose the name “Reunion” because it is fundamentally about
bringing the two worlds together so that this divide doesn’t
exist,” said Steve Kirbach, Microsoft developer working at
Windows UI team.
This project is also supposed to enable UWP development
features for Win32. For example, apps that devs distribute via
MSIX won’t be any different from distributing a UWP app via
“We’re also making it simpler for developers who don’t want to
distribute via MSIX still use features that require what is
known as “package identity” – which is the way the Windows OS
is able to show things like Notifications, or allow your app to
use the Share target,” Microsoft said.
If the idea works, all platforms (Win32 and UWP) will have
access to all features, modern app and touch-ready UI on all
supported versions of Windows 10.