What's new for Windows developers

This section curates the latest platform capabilities, SDK and API additions, AI integration options, performance and diagnostics improvements, design guidance updates, and productivity tooling enhancements. Microsoft refreshes these highlights as new capabilities ship.

Latest SDK and WinUI releases

Find the latest downloads, release notes, and updates for the Windows SDK, Windows App SDK, and WinUI 3.

Versions below are current as of September 30, 2026. Use the release notes to review the changes and requirements for each channel or SDK build.

Highlights – September 2026

SDK releases and developer blog posts

• Windows App SDK 2.5 Experimental (2.5.4-experimental): The September 29 experimental release adds AI compute-device selection, updated speech-recognition and language-model APIs, programmatic theme-resource binding, delegate-based DataTemplate construction, experimental TableView and Chart controls, and updated inking APIs. See the Windows App SDK 2.5 experimental release notes.
• WSL Containers is generally available: Build, run, and deploy Linux containers on Windows by using the wslc.exe CLI, its container.exe alias, or the WSL Containers API. The GA release adds container lifecycle, networking, health-check, storage, Microsoft Defender for Endpoint, and Microsoft Intune capabilities. See WSL Containers now generally available and the WSL Containers architecture deep dive.
• Visual Studio September update: The update introduces Bring Your Own Model in preview, Copilot assistance for NuGet vulnerability fixes, pull-request exploration in the Git agent, improved branch-condition debugging, and Podman support for Attach to Process. See Visual Studio September Update: Power Your Workflow with Your Model.
• Inside MSIX: identify packaged processes: Learn how to use Task Manager's Package name column to distinguish packaged processes from unpackaged processes. See How to tell if a process is packaged.
• Windows App Development CLI 0.7.0: The release adds Windows Sandbox execution, Native AOT support, one-step project packaging, single-file apps with package identity, the winapp find-api command, Reactor templates, and improved UI automation. See WinAppCLI v0.7.0 release announcement.
• Windows App SDK 2.5.1: The September 16 stable release adds support for the windows.diagnosticServiceModule package-manifest extension, limited-access App Content Search APIs for lexical and semantic search scenarios, and reliability fixes across WinUI, input, and composition. See the Windows App SDK 2.5.1 release notes.
• .NET 11 performance improvements: Review runtime, JIT, garbage collection, Native AOT, libraries, and SDK changes that improve application performance in .NET 11. See Performance improvements in .NET 11.
• Intelligent Terminal 0.2.2572: The update includes more than 60 performance and reliability fixes, faster startup and context gathering, API keys for local models, optional automatic approval, and native agent slash commands. See Intelligent Terminal 0.2.2572: Performance & Reliability.
• .NET 11 Release Candidate 1: The September 8 prerelease includes SDK tooling, C# 15, and Windows Forms updates, and comes with a go-live support license. Review the release notes and tool requirements before upgrading. See Announcing .NET 11 Release Candidate 1.
• September .NET servicing updates: Security and non-security updates are available for .NET 10, .NET 9, .NET 8, and .NET Framework. See .NET and .NET Framework September 2026 servicing updates.
• Project Zenith: The September 4 announcement describes a developer-focused Windows experience with preinstalled tools and development settings on new developer-class devices. Initial availability is planned for AMD's Ryzen AI Halo. See Announcing Project Zenith.
• Inside MSIX: servicing packages that are in use: Learn why deployment can return ERROR_PACKAGES_IN_USE, and how application shutdown and deferred updates affect servicing. See Servicing While In Use and ERROR_PACKAGES_IN_USE.
• Inside MSIX: package storage: Learn how PackageVolume manages staged packages, default and offline volumes, and storage on non-system volumes. See MSIX PackageVolume: How Package Storage Works.

Documentation highlights

• WinUI 3 line-of-business apps: A new hub brings together guidance on tabular data, validated forms, database access, design, migration, and AI for business applications. See Build line-of-business apps with WinUI.
• AI-assisted WinUI development: Build a task-tracking app while learning to inspect generated projects, check APIs against Microsoft Learn, and test the resulting UI and data behavior. See Build a WinUI 3 task app with an AI assistant.
• AI-assisted modernization planning: Use an updated, tool-neutral prompt that asks an assistant to inspect an existing desktop app, clarify constraints, and propose an incremental plan grounded in documentation. See Plan your modernization with an AI assistant.
• WinUI XAML Islands: Updated hosting guidance explains how to add Windows App SDK controls to an existing desktop app and distinguishes WinUI XAML Islands from legacy UWP system XAML Islands. See Host WinUI controls with XAML Islands.
• WinUI 3 performance workflow: The performance overview now connects measurement, startup optimization, responsiveness and rendering, and remeasurement, with links to focused guidance for each bottleneck. See Improve your WinUI 3 app's performance.

Highlights – August 2026

• Windows App SDK 2.4 Experimental (2.4.1-experimental): The August 25 experimental release adds inking support for WinUI 3 — the new InkCanvas, InkToolbar, and InkPresenter APIs bring pen and touch input, stroke input, unprocessed input, and clipboard and high-contrast support to WinUI 3 apps. It rolls the 2.4.0 stable changes forward on the experimental channel — Release notes | Install: Microsoft.WindowsAppSDK version 2.4.1-experimental from NuGet
• Windows SDK build 10.0.28000.2705: The latest Windows SDK flight (August 2026) adds new WinRT and Win32 APIs, including Windows.Management.Update scan-mode and software-update identity/category types, RetailInfo.IsDemoModeEnabledEx, ToastNotification.IsExpandableContentSupported, a Direct3D 12 ID3D12DeviceStatistics interface, an AV1 encoder operating-mode codec API, and endorsement-key enrollment v2 cryptography OIDs — Windows SDK release notes | Downloads
• Inside MSIX – What Kind of Packaged Process Is It?: Howard Kapustein breaks down the three kinds of packaged process — Universal, Centennial/Desktop Bridge, and Win32alacarte — and how the RuntimeBehavior manifest attribute (windowsApp, packagedClassicApp, win32App) trades off compatibility against modern packaged behavior — What Kind of Packaged Process Is It?
• PowerToys 0.101: Adds Window Hopper for quickly moving between windows from the same app, a redesigned update experience with Stable and Insider channels, compact mode for Command Palette, on-device Phi Silica transformations in Advanced Paste, and continued WinUI 3 modernization — PowerToys 0.101 release
• AppxManifest IntelliSense in the WinApp VS Code extension: The WinApp VS Code extension now provides IntelliSense — completions, tooltips, and validation — for AppxManifest.xml, making it easier to author package identity and capabilities without leaving the editor — Announcing AppxManifest IntelliSense support
• Windows App SDK 2.4.0: The August 13 stable release adds touchpad and mouse haptics for WinUI 3 apps (via Windows.Devices.Haptics), touchpad single-finger panning on supported hardware, and more precise LanguageModel response statuses — UnsupportedLanguage and LanguageMismatch — so apps can distinguish language errors from generic failures. Also includes targeted reliability fixes for input, Storage Pickers (keyboard focus now restores after a dialog closes), MRT Core, app runtime isolation, and composition — Release notes
• Windows App Development CLI v0.6.0: Adds winapp new to scaffold a WinUI 3 app from official templates with a single command (blank, NavigationView, TabView, MVVM, class library, and unit-test starters), winapp find-ui to search and fetch copy-pasteable XAML and C# samples from WinUI 3 Gallery and Windows Community Toolkit without leaving the terminal, run-from-.csproj with no manual build step, cloud-based artifact signing via Azure, and sparse-package workflow support — WinApp CLI v0.6.0 announcement | Install: winget install Microsoft.WinAppCLI
• Intelligent Terminal 0.2: The biggest release yet of the experimental AI-powered terminal, adding local model support in the Agent Pane, per-tab agent selection with /agent, OpenCode in the built-in agent lineup, WSL agent execution, and a richer Agent Pane UI — Intelligent Terminal 0.2 announcement | Install: winget install Microsoft.IntelligentTerminal
• Inside MSIX – Package Lifetime: How MSIX uses a garbage-collection design for staged package lifetime — why destaging is not a direct result of a single API call, what holds a reference, and when payloads are automatically removed from disk — MSIX Package Lifetime
• The Old New Thing: Raymond Chen's long-running blog on practical Windows development — internals, Win32, shell behavior, and the history behind platform decisions — The Old New Thing

Highlights – July 2026

• Windows App SDK 2.3.1: The July 16 stable release adds the Structured JSON Output API for generating language-model responses constrained to a caller-supplied JSON Schema, the XamlOptionalChanges API for opting into optional breaking changes before XAML initialization, a CompositionEngine API (Limited Access Feature) that apps can use to make the OS the engine for Composition APIs, Video Super Resolution improvements (NPU detection fix + CPU support), ARM64EC support for Windows ML, and a massive batch of XAML performance optimizations — Release notes
• Visual Studio 2026 is here: Now with AI-driven development improvements, integrated Copilot agents for debugging and profiling, and backward compatibility with VS 2022 projects — Visual Studio 2026 announcement
• .NET 11 Preview 6: Features union type support in C#, async validation APIs, AI/agentic workflow enhancements, NativeAOT improvements, and enhanced runtime/JIT performance — .NET 11 Preview 6
• PowerToys 0.100: A milestone release featuring a redesigned Shortcut Guide that detects the active app and shows relevant shortcuts as a side pane, a new Command Palette Extension Gallery for browsing and installing extensions, multi-monitor Dock support, and an upgrade to .NET 10 — PowerToys 0.100 release notes
• WSL Containers: Run Linux containers on Windows by using the new wslc.exe CLI or the Microsoft.WSL.Containers NuGet package, which provides C#, C++, and C projections for programmatically pulling, running, and interacting with Linux containers — including stdin/stdout, file mounts, networking, and GPU access — from your Windows app — WSL Containers overview

Announced at Build – June 2026

• Windows Developer Configurations: Get from a fresh Windows install to a ready-to-code environment in minutes with curated, open-source configuration files for toolchains, OS settings, and shells — Windows Developer Configurations.
• Coreutils for Windows: A collection of essential Unix-style command-line utilities, now available natively on Windows — Coreutils overview.
• Intelligent Terminal: An experimental, open-source fork of Windows Terminal with native agent integration, automatic error detection, and a built-in agent pane for pair-programming in the shell — Announcing Intelligent Terminal version 0.1.
• WSL Containers (public preview): A CLI and API for creating, running, and interacting with Linux containers on Windows. Public preview became available on June 29. See WSL container is now available for public preview.
• Windows Development Skills: Structured knowledge that enables AI agents to build native Windows apps end-to-end by using WinUI 3 skills and WinApp CLI — Get started with Windows Development Skills.

Highlights – June 2026

• Build 2026: Windows as the trusted platform for development: Major announcements including developer-optimized Windows 11 and the Microsoft Execution Containers (MXC) SDK. For additional Build highlights, see Announced at Build – June 2026, earlier in this article — Build 2026 blog post
• Developer-optimized Windows 11: One-command setup for your dev environment with VS Code, GitHub Copilot, WSL, and PowerShell 7. Now generally available.
• Microsoft Execution Containers (MXC) SDK: Secure, policy-driven execution containers that let agent apps set containment boundaries on resources like files and networks.
• Windows App SDK 2.0 features: AI Video Super Resolution API (VideoScaler), ApplicationData for unpackaged apps, XamlBindingHelper improvements, TitleBar custom drag regions, and semantic versioning — Release notes
• Inside MSIX – Staging: Sharing is Caring: Deep dive on how MSIX staging works — pkgdir creation, ACL enforcement, and why the immutability guarantee lets the system safely share the same staged package across all users. Part 1 of a series by Howard Kapustein, MSIX Principal Engineer — Staging: Sharing is Caring

Highlights – May 2026

• Inside MSIX blog: New Microsoft engineering blog with deep dives on MSIX architecture, package identity, deployment operations, and the Stage/Register model — written by Howard Kapustein, MSIX Principal Engineer — Inside MSIX
• WinUI agent plugin for GitHub Copilot and Claude Code: A new plugin with eight specialized skills and a dedicated winui-dev agent for end-to-end WinUI development — scaffold, build, run, test, package, and migrate from WPF — in 70% fewer tokens than generic agents. Install with /plugin install winui@awesome-copilot — Introducing WinUI agent plugin for GitHub Copilot and Claude Code
• dotnet new WinUI templates (preview): New open-source project and item templates for WinUI that let you create and run apps directly from the command line without Visual Studio. Includes Blank, NavigationView, TabView, and MVVM templates, all built around Windows app silhouettes with modern Fluent Design defaults — Introducing dotnet new WinUI templates
• WinApp VS Code extension: Brings the full Windows App Development CLI into VS Code — initialize, run, debug, package, and sign Windows apps from any framework (WinUI, WPF, C++, Electron, Rust, Tauri, Flutter) without leaving the editor — Announcing the WinApp VS Code Extension

Highlights – April 2026

• WinUI 3 Gallery 2.9: First release of WinUI Gallery built on Windows App SDK 2.0, with new control samples, updated defaults, and improvements across the board — Announcing WinUI 3 Gallery 2.9
• Windows App Development CLI v0.3: New winapp run and winapp ui commands, dotnet run support for packaged apps, and a full run-and-debug experience outside Visual Studio. Unlocks agentic scenarios where agents can run, see, and interact with a running Windows app — Windows App Development CLI v0.3
• Agentic AI tools for Windows development: New guide on enhancing AI coding agents with Windows-specific context — including the Microsoft Learn MCP Server for live documentation access, and the WinUI 3 development plugin for GitHub Copilot to generate accurate, modern WinUI 3 code — Agentic AI tools for Windows.
• WinApp CLI cross-framework guides: The Windows App Development CLI (public preview) now has step-by-step guides for adding Windows capabilities to apps built with .NET, C++, Rust, Flutter, Electron, and Tauri — including packaging, identity, AI integration, and notifications — WinApp CLI guides.
• MapControl for WinUI: New documentation for the MapControl, an interactive map powered by Azure Maps with support for pins, layers, and user interaction — MapControl guide.
• Materials documentation: New dedicated pages covering how to use Mica and Acrylic in your WinUI apps — Materials overview and In-app acrylic.
• Store API updates: New sections documenting how to check whether an unpackaged app is installed and how to open the Store product detail page for a product — Send requests to the Store.
• Iconography documentation reorganized: App icon and iconography docs now live in a dedicated Iconography hub for easier navigation.
• Windows notifications overview: Confused by AppNotificationManager vs ToastNotificationManager? New overview page explains which notification API to use for your app type, with a feature comparison table and links to samples — Windows notifications overview.
• Performance docs for WinUI: The full set of Windows app performance documentation — startup, memory, XAML layout, animations, ListView/GridView optimization, and more — is now available under the WinUI developer section at Windows app performance.
• Visual layer and Composition docs for WinUI: Documentation for the Visual layer (Microsoft.UI.Composition) — including visuals, animations, effects, brushes, lighting, and shadows — is available in the WinUI/Windows App SDK developer section at Visual layer overview.
• Command Palette extension toolkit: New API reference documentation for the PowerToys Command Palette extension toolkit, covering built-in commands (CopyPathCommand, OpenFileCommand, OpenInConsoleCommand, and more) and layout types — Command Palette extension toolkit.
• Java getting started for Windows: New guide for setting up a Java development environment on Windows, covering JDK installation, JAVA_HOME configuration, editor options, and WSL considerations — Java on Windows.
• Windows app development overview: Landing page for Windows app capabilities, with entry points to accessibility, AI, files, notifications, UI, and more — Windows app development overview.
• PowerToys 0.99: New Power Display utility for controlling monitors from the system tray, Grab And Move for resizing windows from anywhere, and improvements to Command Palette and the Dock — PowerToys 0.99 release — Microsoft PowerToys: Utilities to customize Windows.
• Windows Terminal 1.25: New settings page for extensions, improved multi-language Command Palette suggestions, and a completely rebuilt windowing architecture with more reliable tray icon and Quake mode — Windows Terminal 1.25 release
• Segoe Fluent Icons Font updated: The Segoe Fluent Icons Font documentation now includes the latest icon additions and usage guidance — View icons.
• WinUI terminology clarification: Updated terminology across documentation for clarity — "WinUI 2" is now "WinUI for UWP" and "WinUI 3" is now just "WinUI" to reflect current naming conventions.
• Windows Developer Support hub: New centralized support page with quick help actions, community channels, and Microsoft support contacts — Get support.
• Windows App SDK release notes: Refactored and consolidated history from 0.5 through 2.0 — find the latest fixes and APIs in one place (release notes hub).
• Windows SDK updates: New overview and detailed release notes to track SDK changes (overview · release notes).
• WinAppCLI public preview: The Windows App Development CLI is a command-line interface for managing Windows SDKs, packaging, generating app identity, manifests, certificates, and using build tools with any app framework — (GitHub repo).
• Cross Device Resume (XDR) overview: Introduces Windows app continuity across devices and technologies available to enable XDR scenarios (overview).
• Implement XDR using WNS raw notifications: Step-by-step guide to integrate app continuity via WNS, including prerequisites and Python/JavaScript examples (how-to).
• AI on Windows: Fresh overview for building AI‑powered experiences on Windows, with entry points to APIs and tooling (Windows AI overview).
• Packaged vs. unpackaged guidance: Updated guidance for choosing and configuring packaged or unpackaged apps, including WinUI scenarios (decision guide).
• UWP capability declarations: Revised topic clarifying capability types, privacy‑sensitive capabilities, and Store submission considerations (declare capabilities).
• Microsoft Store: The latest news from the Microsoft Store including waived fees and updated analytics.

Windows app development documentation and resources