Microsoft is working on optimizations for WinUI 3 designed to make Windows applications faster and more efficient. According to the company, the changes will result in lower memory usage and a more responsive user experience. The company is also attempting to address an issue with the modern Windows framework: criticism from developers regarding the performance of WinUI 3.
The improvements were announced via GitHub, where Microsoft shared figures on the impact of the optimizations. For the part of File Explorer that runs on WinUI 3, the company reports, among other things, 41 percent fewer memory allocations and 45 percent fewer function calls. Additionally, the time spent in WinUI code is said to have decreased by approximately 25 percent.
According to Microsoft, some optimizations will initially be made available as optional, as certain changes could cause compatibility issues for existing applications. Ultimately, the improvements are set to become a standard part of WinUI and the Windows App SDK.
More Windows Components Moving to WinUI 3
The optimizations are part of a broader strategy to make Windows faster and more consistent. Earlier, Windows executive Pavan Davuluri indicated that Microsoft is working on a faster and more reliable File Explorer. In addition, the company aims to incorporate more components of Windows into WinUI 3.
According to DevClass, however, developers have mixed reactions to that ambition. Although WinUI 3 is Microsoft’s modern UI framework for Windows 11 and supports Fluent UI, many developers still find the platform relatively heavy and slow.
In comments on GitHub, several developers state that WinUI 3 currently runs noticeably slower than older Windows technologies such as WPF and UWP. Some point out that modern Windows components, including File Explorer, still regularly suffer from delays and glitches.
Architecture remains a point of contention
Some of the criticism focuses on the technical foundation of the framework. WinUI 3 is based on WinRT, the Windows Runtime layer that Microsoft introduced during the Windows 8 era. As a result, the framework sits between application code and the classic Win32 API.
DevClass reports that some developers view that extra layer of abstraction as a major cause of the performance issues. Component vendor DevExpress also previously pointed out slowdowns caused by WinRT interoperability within WinUI 3.
The discussion also touches on a broader frustration within the Windows developer community. In recent years, Microsoft has introduced multiple UI frameworks side by side, while various internal teams did not always adopt those technologies consistently. This regularly led to fragmentation between older and newer Windows interfaces.
With the new optimizations, Microsoft is attempting to demonstrate that WinUI 3 must be made suitable for larger-scale use within Windows itself. Whether that will be enough to regain developers’ trust will depend largely on practical experiences with applications such as File Explorer.