> ## Documentation Index
> Fetch the complete documentation index at: https://docs.xbox.com/llms.txt
> Use this file to discover all available pages before exploring further.

# What's new in the Microsoft Game Development Kit (GDK)

> Highlights features, tools, and documentation introduced in supported Microsoft Game Development Kit releases.

> [tab] GDK 2610
>
> ## What's new in the October 2026 Microsoft Game Development Kit
>
> The Microsoft Game Development Kit (GDK) is a complete set of tools, APIs, extensions, and programming models that can be used across current and future Microsoft Gaming platforms and initiatives. The GDK's design and features are driven by your feedback about how you like to develop games. For a complete introduction, see [Welcome to the Microsoft Game Development Kit](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/intro/welcome).
>
> In addition to many bug fixes, this release includes the following new features.
>
> ## Table of contents
>
> [Packaging](#packaging)\
> [Developer tools](#developer-tools)\
> [GDK](#gdk)\
> [AMD FSR™ Upscaling 4](#amd-fsr-upscaling-4)\
> [Samples](#samples)
>
> ***
>
> ### Packaging
>
> #### MSIXVC2 for PC games
>
> MSIXVC2 is now the default PC packaging format. Building on the preview introduced in the April 2026 (2604) GDK, MSIXVC2 is now the default for games built with the Microsoft GDK and is fully supported across the publishing, ingestion, licensing, and download stack.
>
> Key general availability (GA) improvements include the following:
>
> * **Version-aware licensing**. Per-version encryption keys flow through CELS and Catalog.
> * **Production-scale ingestion**. Hardened deduplication, version validation, integrity checks, and scan workflow scale.
> * **Platform GA**. Retail-ready download, install, and update on PC, with full Gaming Services integration.
> * **Telemetry parity**. Install and network speed reports cover MSIXVC2 alongside MSIXVC1.
> * **Middleware enablement**. Unity and Unreal engine paths for MSIXVC2 packaging. 
> * **XPlaytest support**. The playtest publishing pipeline supports MSIXVC2 packages end-to-end.
>
> #### Publisher Content packages
>
> PC and console games can now ship Publisher-hosted Content, a new package type that lets game publishers host and update content on their own CDNs while the platform continues to manage installation, background download, integrity, and the user experience.
>
> For more information, see [Publisher Content packages](https://learn.microsoft.com/en-us/gaming/gdk/docs/features/common/packaging/packaging-publisher-content).
>
> ***
>
> ### Developer tools
>
> #### XBOX Test Account CLI
>
> `XblTestAccount.exe`, new in the October 2026 GDK, signs an XBOX test account in to a sandbox once, caches the credential, and then reads or changes the account's privileges and privacy settings without any UI. Use it to script restricted-account tests, such as blocking privilege 254 (Multiplayer Sessions) to check how your title responds, or to sign accounts in ahead of time so `XblPlayerDataReset.exe` can run unattended.
>
> #### PIX
>
> A new command-line tool, `convertpevt.exe`, converts `.pevt` offline timing captures from XBOX Series X|S consoles into `.xpix` captures without opening PIX, so programmatic captures taken with `PIXBeginCapture` can be processed in automated workflows. The tool is installed in the GDK `bin` folder; run `convertpevt --help` for usage, options, and exit codes. Also available in the April 2026 GDK Update 3. \[62625022]
>
> ***
>
> ### GDK
>
> #### GDK layout deprecation
>
> The October 2025 and April 2026 GDK releases include both the simplified and legacy layouts. Beginning with the October 2026 GDK, setup installs only the simplified layout by default. The legacy layout can still be selected as an optional installation, but it is deprecated and is no longer the recommended development path.
>
> The legacy layout will no longer be supported and will be removed from the installer starting with the April 2027 GDK release.
>
> #### AMD Compiler (ACO) in GDK
>
> Experimental new shader compiler for XBOX consoles (XBOX Series X|S) based on ACO from Mesa
>
> XBOX is working to bring further optimizations to game developers' shader compilation and runtime performance via an experimental new shader compiler. Developers can use this compiler as an optimization tool and may find significant improvements in compilation and runtime performance compared with the standard XBOX shader compiler. In our initial testing and evaluation, developers have seen improvements in the range of 2-16%, depending on game engine, content, and current shader bottlenecks. Please see the documentation and [samples](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/development-downloads/gdk-samples-home) for more information and connect with us via the developer forums or your developer account manager.
>
> ***
>
> ### AMD FSR™ Upscaling 4
>
> The new [AMD FSR GDK sample](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/development-downloads/gdk-samples-home) demonstrates how to leverage [AMD FSR™ Upscaling 4.1.2](https://gpuopen.com/amd-fsr-upscaling/), bringing AMD’s ML-based upscaling to XBOX Series X|S for the first time. It includes AMD’s Full INT8 model and a new Lite INT8 model that is less than half the size and has a lower upscaling cost, so XBOX developers can choose the balance of GPU performance and visual quality that best fits each title. In collaboration with AMD, XBOX has optimized the implementation for both consoles, delivering outstanding performance while preserving both models’ full capabilities and enhanced image quality over AMD FSR 3. These XBOX-specific optimizations deliver higher upscaling throughput per teraflop than AMD RDNA 2 architecture PC GPUs running the same Full INT8 model, giving developers an efficient way to turn lower-resolution rendering into a high-quality final frame. 
>
> ***
>
> ### Samples
>
> For a complete list of samples included with the Microsoft Game Development Kit (GDK), see [Microsoft Game Development Kit samples](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/development-downloads/gdk-samples-home).

> [tab] GDK 2604
>
> ## What's new in the April 2026 Microsoft Game Development Kit
>
> The Microsoft Game Development Kit (GDK) is a complete set of tools, APIs, extensions, and programming models that can be used across current and future Microsoft Gaming platforms and initiatives. The GDK's design and features are driven by your feedback about how you like to develop games. For a complete introduction, see [Welcome to the Microsoft Game Development Kit](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/intro/welcome).
>
> In addition to many bug fixes, this release includes the following new features.
>
> ## April 2026 table of contents
>
> [Developer tools](#developer-tools)\
> [Packaging](#packaging)\
> [System](#system)\
> [Samples](#samples)
>
> ***
>
> ### Developer tools
>
> #### Visual Studio 2026 GDK support
>
> Beginning with the April 2026 GDK, Visual Studio 2026 is now supported for GDK development. Both the Professional edition and the Enterprise edition are supported.
>
> Visual Studio project templates are available as follows.
>
> * Console development templates are installed by the GDK.
> * PC development templates can be installed from [Microsoft GDK Templates](https://aka.ms/gdktemplates).
>
> Visual Studio 2026 introduces a new servicing and support model based on yearly releases and a two-year servicing timeline. For more information, see [Visual Studio Product Lifecycle and Servicing](https://docs.xbox.com/visualstudio/releases/2026/servicing-vs).
>
> For more information about Visual Studio 2026, see [Visual Studio 2026 is here: faster, smarter, and a hit with early adopters](https://devblogs.microsoft.com/visualstudio/visual-studio-2026-is-here-faster-smarter-and-a-hit-with-early-adopters/).
>
> #### MSIXVC2 packaging format preview
>
> MSIXVC2 is a new packaging format for PC games built with the GDK. It delivers significantly smaller base game packages and content updates, faster packaging, and a simplified upload workflow as compared to the original MSIXVC format. MSIXVC2 is available as a preview starting with the April 2026 GDK.
>
> Key improvements include the following:
>
> * **Smaller content updates**. Byte-level change tracking eliminates alignment padding and chunk-boundary constraints, reducing update sizes by 64–94% compared to MSIXVC.
> * **Faster packaging**. makepkg2 pack delivers 2x–8x speedups, depending on title size.
> * **Reduced package overhead**. Over 90% reduction in fixed hash-tree overhead; supports partial download instead of full re-download with every update.
> * **Built-in compression**. Transparently compresses assets for transport and storage; installed uncompressed on the player's device.
> * **One-command upload**. Combines packaging and uploading into a single step with makepkg2 upload.
>
> For more information, see [PC packaging improvements](https://learn.microsoft.com/en-us/gaming/gdk/docs/features/common/packaging/overviews/packaging-msixvc2-overview).
>
> > [!NOTE]
> >
> > We recommend not using this new packaging format in production. MSIXVC2 submissions to the public will be blocked by certification tests until the general availability (GA) release, which is currently targeted for the October 2026 GDK.
>
> #### Submission Validator update
>
> Submission Validator version 10.0.26100.7798 is now available. Download the latest version from [https://aka.ms/currentsubvalzip](https://aka.ms/currentsubvalzip).
>
> > [!NOTE]
> >
> > Starting with this release, the legacy download location at aka.ms/gdkdl has been retired. Submission Validator is now available exclusively from [https://aka.ms/currentsubvalzip](https://aka.ms/currentsubvalzip). The previous version (10.0.26100.6877) remains valid until April 30, 2026.
>
> > [!NOTE]
> >
> > As announced in March 2025, updating Submission Validator is now simplified. Programmatic, unauthenticated updates are available directly in your pipeline. For download and update instructions, see [Updating Submission Validator](https://learn.microsoft.com/en-us/gaming/gdk/docs/features/common/packaging/subval/submissionvalidator#updating-submission-validator).
>
> This release includes the following changes.
>
> * **MSIXVC2 developer preview packages now report a FAILURE.** Submitting MSIXVC2 packages to certification isn't supported during the preview period. This aligns with the certification test block that's described in the [MSIXVC2 packaging format preview](#msixvc2-packaging-format-preview) section above.
> * `ILI_ArchitectureArm64Mismatch` no longer reports a FAILURE for Arm64EC (emulation compatible) binaries.
> * The `ILI_ArchitectureAmd64Mismatch` and `ILI_ArchitectureX86Mismatch` warnings now only apply to executables that are listed in the MicrosoftGame.config file.
> * If Submission Validator encounters a crash during symbol bundling, it now reports an `ILI_SymbolHandlingInitError` INFO message and continues validation instead of exiting early.
>
> #### XblPcSandbox.exe command-line tool improvements
>
> The `XblPcSandbox.exe` command-line tool now has quality-of-life improvements to enhance the sandbox-switching experience for PC game developers.
>
> Key improvements include the following:
>
> * **Clearer sandbox switch output**. `XblPcSandbox.exe` now displays the current sandbox value before and after a switch operation. This display makes it immediately obvious if the intended sandbox was applied. In addition, an indeterminate progress spinner is now available to show when the tool is actively working. 
> * **New /retail switch**. A dedicated `/retail` command-line option is now available to make it easier to switch your PC back to RETAIL mode. Previously, this was only documented as passing RETAIL as the sandbox name, which could be missed.
> * **Automatic sandbox casing correction**. The sandbox switching logic now automatically corrects the casing of sandbox names (for example, retail to RETAIL). This logic reduces errors that are caused by case sensitivity. Most sandbox names are in all capital letters.
> * **New /feedback switch**. A `/feedback` option is now available that deep links directly to the Feedback Hub, making it easier to report issues or provide feedback about the sandbox-switching experience.
> * **Enhanced Help text with troubleshooting guidance**. The Help usage text now includes troubleshooting suggestions and a link to the troubleshooting documentation. Solutions to common sandbox issues are now available directly from the command line.
>
> For more information, see [PC Sandbox Switcher (XblPCSandbox.exe)](https://learn.microsoft.com/en-us/gaming/gdk/docs/tools/tools-services/live-pc-sandbox-switcher).
>
> #### XBOX PIX support for file mapping in DirectStorage events
>
> XBOX PIX now supports packaged file mapping in DirectStorage events. This matches the existing File IO event mapping behavior and properly indexes the list of files along with their offsets and descriptions.
>
> #### Flexible MicrosoftGame.config Editor
>
> MicrosoftGame.config Editor no longer enforces game configuration schema validation when opening files. If a file is valid XML, the editor attempts to load it by using the correct node structure, even if the configuration itself is invalid. This allows invalid configuration files to be opened and fixed in the editor instead of failing to load.
>
> ***
>
> ### System
>
> #### Native ARM64 build GDK support preview
>
> The GDK now supports a preview of native ARM64 build libraries for binaries that ship with the GDK. These binaries include the [PlayFab Unified SDK (v2)](https://docs.xbox.com/gaming/playfab/sdks/unified-sdk/overview.md), the XBOX Services API, the XBOX Authentication Library, Game Chat 2, and `xCurl`. This support enables you to produce fully native ARM64 game builds.
>
> For more information see, [A simplified GDK directory structure](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/pc-dev/overviews/gdk-new-layout).
>
> > [!NOTE]
> >
> > This preview is intended for testing only. We recommend not using it in production.
>
> #### GDK layout deprecation
>
> The October 2025 and April 2026 GDK releases include both the simplified and legacy layouts. Beginning with the October 2026 GDK, setup installs only the simplified layout by default. The legacy layout can still be selected as an optional installation, but it is deprecated and is no longer the recommended development path.
>
> The legacy layout will no longer be supported and will be removed from the installer starting with the April 2027 GDK release.
>
> ***
>
> ### Samples
>
> For a complete list of samples included with the Microsoft Game Development Kit (GDK), see [Microsoft Game Development Kit samples](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/development-downloads/gdk-samples-home).

> [tab] GDK 2510
>
> ## What's new in the October 2025 Microsoft Game Development Kit
>
> The Microsoft Game Development Kit (GDK) is a complete set of tools, APIs, extensions, and programming models that can be used across current and future Microsoft Gaming platforms and initiatives. The GDK's design and features are driven by your feedback about how you like to develop games. For a complete introduction, see [Welcome to the Microsoft Game Development Kit](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/intro/welcome).
>
> Watch the following video for a quick look at what's new in the October 2025 GDK.
>
> > [Watch the GDK update video](https://aka.ms/GDK-WhatsNewVideo)
>
> Release notes for the current release of the GDK can be found in the [GDK/XDK Release notes space](https://aka.ms/gdkreleasenotes) on the XBOX Developer Forums.
>
> In addition to many bug fixes, this release includes the following new features.
>
> > [!NOTE]
> >
> > This article includes features that are public. For What's New information that requires NDA access, see [What's new in the October 2025 Microsoft Game Development Kit - NDA Features](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/whatsnew/2510/whats-new-nda-2510).
>
> ## October 2025 table of contents
>
> [Developer tools](#developer-tools)\
> [Input](#input)\
> [System](#system)\
> [Microsoft Azure PlayFab](#microsoft-azure-playfab)\
> [Samples](#samples)
>
> ***
>
> ### Developer tools
>
> #### Submission Validator automatic updates
>
> Use the `/updatesubval` flag on `MakePkg` to check for a new version of Submission Validator. If it's available, the .zip file is downloaded and extracted, and the new version of SubmissionValidator.dll is copied to the `bin` directory (or to an alternate location if `/subvalpath` is specified).
>
> #### XBOX Game Package Manager
>
> XBOX Game Package Manager (XGPM) is a new desktop app that streamlines packaging XBOX games (in both XVC and MSIXVC) and uploading them to Microsoft Partner Center.
>
> **Features**
>
> * **Unified tooling:** Combines the functionality of `MakePkg` and `PackageUploader` into a single, intuitive UI.
> * **Smart packaging:** Automatically builds packages from loose files by using your installed GDK, creates default layouts for packaging, and supports custom overrides.
> * **Simplified uploads:** Select your package, branch, and market group, and then upload them by using browser-based authentication, no client secrets or certificates are required.
> * **Multi-tenant support:** Ideal for scenarios where XBOX games are codeveloped.
> * **Accessibility and localization:** Fully supports narrator, high contrast, and tab-index navigation. Has a localized UI in en-US, ja-JP, zh-CN, and ko-KR.
>
> #### wdcapturesession PC command-line tool
>
> `wdcapturesession` is a new PC command-line tool for recording live video captures during game tests. This tool uses H264/High Efficiency Video Coding (HEVC) encoding at 30 frames per second (fps) to start and stop game captures on PC.
>
> #### MicrosoftGame.config schema updates
>
> The schema for the MicrosoftGame.config file has been updated to support the specification of an ARM64 binary alongside the x64 binary in a game's package. 
>
> A new `architecture` attribute has been added to the `Executable` element to specify whether the executable is an ARM64 binary or an x64 binary. The Microsoft Game Config Editor has been updated to support this new attribute.
>
> #### Visual Studio 2026 Insiders compiler and linker
>
> [Visual Studio 2026 Insiders](https://devblogs.microsoft.com/visualstudio/visual-studio-2026-insiders-is-here/) is now available. The October 2025 GDK has a set of MSBuild files for building your game with the Visual Studio 2026 Insiders compiler and linker. These files are in the `<GDK edition>\xbox\build\vs2026` folder.
>
> #### Visual Studio project templates
>
> Visual Studio project templates have been removed from the GDK installer. Modern functional replacements can now be downloaded at [https://aka.ms/GDKVSExtensions](https://aka.ms/GDKVSExtensions).
>
> ***
>
> ### Input
>
> #### GameInput updated on console
>
> `GameInput` has been updated on console to support the latest features that are available on PC. For more information, see [Overview of GameInput](https://aka.ms/gameinput).
>
> ***
>
> ### System
>
> #### Cross-platform Gaming Runtime
>
> The cross-platform gaming runtime allows games on different storefronts (for example, Steam) and devices
> (for example, Steam Deck) to easily incorporate Microsoft Gaming Services into their game.
> The cross-platform gaming runtime allows developers to link a module into their game that enables:
>
> * XBOX sign-in
> * XBOX profile information
> * XBOX friends list
> * XBOX presence
> * XBOX game invites
>
> The cross-platform gaming runtime also supports cross-progression using
> **PlayFab Game Saves**. On Windows devices, game saves are seamlessly uploaded
> outside of the game’s lifetime. On other devices, such as Steam Deck, that don’t support
> out-of-game lifetime upload, upload happens within the game, using the same API calls.
> PlayFab Game Saves supports XBOX, Steam, and publisher-based player identities.
>
> > [!NOTE]
> >
> > The use of XBOX cross-platform services in non-Microsoft storefronts may require the game to seek permission from the storefront owner.
>
> #### GDK installer directory structure layout UX
>
> This release of the GDK contains a new directory structure layout UX of the GDK installer to simplify the developer experience and enable future extensibility. It simplifies integration, supports a growing list of target platforms, and improves the support for both stock MSBuild platforms and non-Microsoft build systems.
>
> The October 2025 and April 2026 GDK releases include both the simplified and legacy layouts. Beginning with the October 2026 GDK, setup installs only the simplified layout by default. The legacy layout can still be selected as an optional installation, but it is deprecated and is no longer the recommended development path.
>
> The legacy layout will no longer be supported and will be removed from the installer starting with the April 2027 GDK release.
>
> ***
>
> ### Microsoft Azure PlayFab
>
> #### PlayFab Unified SDK
>
> The PlayFab Unified SDK is now included with the GDK. This SDK combines components from previously separate SDKs into a single, modernized package. It delivers consistent APIs, modern memory and thread handling, and automatic token refresh.
>
> This SDK builds on improvements that were introduced in the 2023 PlayFab Services C/C++ SDK and extends them across all PlayFab components. The PlayFab Unified SDK uses a modular design. This enables you to integrate only the features that your project needs while providing a more streamlined and reliable development experience.
>
> For more information, see [PlayFab Unified SDK](https://docs.xbox.com/gaming/playfab/sdks/unified-sdk/overview.md)
>
> #### PlayFab Game Saves
>
> PlayFab Game Saves is now available, starting with XBOX and Steam. This feature enables players to continue their game, with their progress intact, as they switch platforms, devices, and stores.
>
> Game Saves handles file synchronization and conflict resolution, helps players maintain a single point of progression, and fully supports offline play. To request Game Saves access, select your title in [PlayFab Game Manager](https://developer.playfab.com/), navigate to Progression | Game Saves, and then join the waiting list. For more information, see the [Game Saves documentation](https://aka.ms/playfab-game-saves).
>
> ***
>
> ### Samples
>
> For a complete list of samples included with the GDK, see [Microsoft Game Development Kit samples](https://learn.microsoft.com/en-us/gaming/gdk/docs/gdk-dev/development-downloads/gdk-samples-home).


## Related topics

- [Release notes for the Microsoft Game Development Kit (GDK)](https://docs.xbox.com/announcements/gdk/release-notes.md)
- [Get started with the Microsoft Game Development Kit (contents)](https://docs.xbox.com/home/setup-install/get-started.md)
- [Microsoft Game Development Kit (GDK) porting guides](https://docs.xbox.com/home/build-first-title/porting-guides.md)
- [Microsoft Game Development Kit samples](https://docs.xbox.com/home/setup-install/samples.md)
- [Using Clang with the Microsoft Game Development Kit (GDK)](https://docs.xbox.com/tools/tools-pc/visualstudio/gr-vs-clang.md)