Microsoft’s Project Reunion to unify app development for over 1 billion Windows devices

It is expected to offer a shared platform for new app development and to update existing apps with the latest functionalities, writes Kevin Gallo, Corporate Vice President, Windows Developer Platform, in a company blog post

Microsoft announced its Project Reunion at Microsoft Build 2020, a digital-only, annual developers conference on May 19. The idea is to unify the app development process for all the current and future apps for over 1 billion Windows devices by bridging the gap between Win32 (Windows API) and UWP (Universal Windows Platform) APIs.

“Project Reunion is our vision for unifying and evolving the Windows developer platform to make it easier to build great apps that work across all the Windows 10 versions and devices people use,” writes Kevin Gallo, Corporate Vice President, Windows Developer Platform, in a company blog post.

It will offer a shared platform for new app development and to update existing apps with the latest functionalities, whether they’re C++, .NET (including WPF, Windows Forms, and UWP) or React Native, writes Gallo.

Microsoft has been using the Win32 API as the main interface between outside applications and the system for many years and it is compatible with a greater number of devices running on many versions of Windows. The UWP API primarily works with devices running on Windows 10. Apps developed using UWP were designed to work with Windows platforms such as Windows Phone, Windows Tablet, HoloLens, and Xbox.

Under Project Reunion, developers will be able to directly use the newest version of Win32 with the app they are developing, with the open-source package manager NuGet, avoiding any compatibility issue with the operating system. WinUI 3 Preview 1, and WebView 2 are two components that will drive the unification process.

User interface technology

WinUI is Microsoft’s user interface technology used for building Windows apps. WinUI 3 Preview 1 can be used in both UWP and Desktop apps, and it supports .NET when run in desktop context.

Using WebView, a Windows app can display web content from within the app. WebView2 allows any Windows app to embed web content with the power of Microsoft Edge and Chromium. It offers new .NET preview and works across the spectrum of Windows apps.

The transition towards a unified Windows platform had already started last year, when the company said it would support the use of Win32 for game development. For years, Microsoft developers had been using UWP for the development of games and other apps for Microsoft’s Windows app store. As all versions of Windows 10 support Win32 — an app developed using it can have a wider reach.

“We recognize that Win32 is the app format that game developers love to use and gamers love to play, so we are excited to share that we will be enabling full support for native Win32 games to the Microsoft Store on Windows,” wrote Phil Spencer, Head of Xbox, in a company post. “This will unlock more options for developers and gamers alike, allowing for the customization and control they’ve come to expect from the open Windows gaming ecosystem,” he added.

Microsoft intends to make the app development process more streamlined for developers, and it plans on using GitHub for engaging with the them.

During a live streaming session, Microsoft CEO, Satya Nadella said: “GitHub is the home for developers, it is where developers build software together. Fifty million developers use GitHub, and they are more active than ever.”

“We are building the most complete tool-chain for developers, bringing together the best of GitHub, Visual Studio, and Azure to help you to go from idea to code, and code to Cloud,” Nadella added.

Microsoft Windows 10 is used in over 1 billion devices, a landmark it reached in March, with the help of Project Runway, it plans on developing apps and updating them, supporting all devices running on latest as well as older versions of Windows 10.