What’s XamlCompiler.exe (Microsoft.UI.Xaml.Markup.Compiler)? Is it safe or a virus?

XamlCompiler.exe is an executable developed by Microsoft Corporation, primarily associated with the compilation of XAML (Extensible Application Markup Language) files in various application development frameworks.

XAML is extensively used for designing user interfaces in technologies such as Windows Presentation Foundation (WPF), Universal Windows Platform (UWP), and .NET Multi-platform App UI (.NET MAUI).

The role of XamlCompiler.exe is to process XAML files, converting them into a binary format that the application can utilize at runtime. This compilation process enhances performance by enabling early detection of errors and reducing the load time of XAML elements.

In development environments like Visual Studio, XamlCompiler.exe operates as part of the build process, ensuring that XAML-based user interfaces are correctly compiled and integrated into the application.

While it functions seamlessly in the background during standard development workflows, developers might encounter it directly when addressing build issues or configuring build processes. For instance, in .NET MAUI applications, XAML compilation is enabled by default to improve performance and catch errors at compile time

Researched by Carl @ SpyShelter Labs