reactor-app

Name: reactor-app
Availability: InStock
Author: Microsoft

Build WinUI 3 desktop apps with Reactor's declarative C# projections.

609|44|Updated Apr 16, 2026

Search Tags:#csharp #declarative #dsl #reactor #ui-framework #winui3

Ready to run

npx skills add https://github.com/microsoft/microsoft-ui-reactor --skill reactor-app

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Please help me install this Agent Skill.
Skill: reactor-app
Source: https://github.com/microsoft/microsoft-ui-reactor/tree/main
Command: npx skills add https://github.com/microsoft/microsoft-ui-reactor --skill reactor-app

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Create WinUI 3 desktop applications using Reactor's declarative C# projection to replace XAML, code-behind, and MVVM boilerplate with a simple, self-contained approach.

Core Features & Use Cases

Declarative UI model: describe UI as immutable element trees and rely on a reconciler to patch real WinUI controls.
Hooks-based state management: co-locate state with render logic using UseState, UseEffect, UseReducer, and related hooks.
DSL-driven UI construction: leverage factory methods and fluent modifiers to build layouts without XAML.
Use cases: rapid prototyping, dashboards, data-driven UIs, and scenarios where developer productivity and type safety matter.

Quick Start

Install the reactor plugin, bootstrap a sample reactor app using mur pack-local, and run ReactorApp.Run<MyApp>("Title") to launch a WinUI 3 window.

Frequently Asked Questions about reactor-app

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I build WinUI 3 desktop apps without using XAML and MVVM boilerplate?▼

You can build WinUI 3 desktop apps without XAML by using C# Reactor to declare UI as immutable element trees, replacing code-behind and MVVM boilerplate with a self-contained declarative approach.

What is declarative UI development in WinUI 3 and how does state management work?▼

Declarative UI in WinUI 3 describes interfaces as immutable trees patched by a reconciler, while state is co-located with render logic using hooks like UseState, UseEffect, and UseReducer.

Can I use Reactor hooks like UseState and UseEffect for state management in WinUI 3?▼

Yes, you can use Reactor hooks like UseState, UseEffect, and UseReducer to co-locate state management directly with render logic when building WinUI 3 desktop applications.

Does C# Reactor support rapid prototyping and data-driven UIs for WinUI 3?▼

C# Reactor supports rapid prototyping, dashboards, and data-driven UIs by leveraging a DSL-driven UI construction model that ensures developer productivity and type safety without XAML.

What's the best way to interop with native WinUI controls using a declarative C# DSL?▼

The best way to interop with native WinUI controls declaratively is using C# Reactor, which employs a reconciler to patch real WinUI controls from immutable element trees described via factory methods.

Why should I replace XAML with a declarative C# projection for WinUI 3 development?▼

You should replace XAML with a declarative C# projection to eliminate MVVM boilerplate, co-locate state with render logic using hooks, and build type-safe UIs with fluent DSL modifiers.