D2R Prep Assistant for Windows (Early Access)

Overview

D2R Prep Assistant is an independently developed, open-source desktop companion utility for Windows 10 and 11 (64-bit). It automates the local environment preparation and packaging workflow for the upstream open-source project, allowing players to produce an unsigned iOS package (.ipa) from their own legally owned Nintendo Switch game files without owning a Mac or installing Xcode.

The project is released under the MIT License and maintained by @0xdcc on GitHub.

Product Boundaries

• Not the game itself: The assistant contains no game assets, copyrighted binaries, textures, audio archives, or decryption keys (prod.keys).
• No Apple credentials: The application never prompts for, stores, or transmits your Apple ID or passwords.
• 100% Local: No files are uploaded to any server or cloud service. All processing occurs locally on your machine.
• Unsigned output: The generated .ipa is unsigned. Sideloading and certificate signing must be performed separately using tools like Sideloadly.
• Windows x64 only: Version 0.1.0 is distributed solely for Windows 64-bit systems. macOS assistant packages are not offered in this release.

Release Details & Download

The official release archive is distributed as an unsigned ZIP:

To verify file integrity after downloading in PowerShell:

Get-FileHash D2R-Prep-Assistant-0.1.0-win32-x64-unsigned.zip -Algorithm SHA256

Confirm that the returned hash matches ac116f220933e5821e42b09d5d3124ba028979e15988518fe8467356ae8463fc.

Windows SmartScreen Notice

Because this is an unsigned community release, Windows Defender SmartScreen may present a security banner when launching the executable:

Windows protected your PC
Microsoft Defender SmartScreen prevented an unrecognized app from starting. Running this app might put your PC at risk.

How to Proceed

1. Check that the file came from the linked project release and compare its SHA-256 with the published value.
2. Review the source and decide whether you trust this early-access release. A checksum verifies file integrity, not safety.
3. If you choose to proceed, Windows may offer More info → Run anyway. Managed devices may block this option.
4. Do not disable antivirus or Windows security software. If security software reports a specific threat, stop and investigate rather than bypassing the alert.

System Requirements & Prerequisites

Before running the assistant, ensure your computer meets these requirements:

1. Operating System: Windows 10 (version 1909 or later) or Windows 11 (64-bit).
2. Free Disk Space:
3. Approximately 0.8–1 GB of initial tool downloads, plus several gigabytes for their extracted files and build caches.
4. Tens of gigabytes free (more may be needed depending on your input size) on your working drive for temporary staging, Switch asset copying, shader translation caches, and intermediate build outputs.
5. Network Connection: High-speed internet connection to download hash-locked portable packages from official endpoints (GitHub Releases, Microsoft .NET NuGet, PyPI).
6. Legitimate Game Files:
7. Nintendo Switch update 1.0.34.0 (internal build 3.3.94012) and the Reign of the Warlock expansion, dumped from your personal console.
8. Must contain ExeFS (main, sdk, subsdk0) and RomFS/data (including build_manifest.psv and 18 non-empty .data archives).
9. Encrypted .nsp, .xci, or standalone console keys (prod.keys) are not accepted.

Step-by-Step Usage Guide

Step 1: Extract the Full Archive

Do not attempt to run D2RPrepAssistant.exe from inside the ZIP file.

1. Right-click D2R-Prep-Assistant-0.1.0-win32-x64-unsigned.zip and select Extract All....
2. Extract the entire folder structure to a local drive with sufficient free space (for example, C:\Tools\D2RPrepAssistant).
3. Open the extracted folder and launch D2RPrepAssistant.exe.

Step 2: Choose Target & Output

1. Select your target iOS generation:
2. iOS 18: For iPhone and iPad devices running iOS/iPadOS 18 through 25.
3. iOS 26: For devices running iOS/iPadOS 26 or later.
4. Select an empty or dedicated Output Folder where the completed .ipa will be placed.

Step 3: Provide Switch Game Files

Select the parent directory that holds your dumped Switch 1.0.34.0 game files. The assistant verifies:

• The ExeFS directory contains main, sdk, and subsdk0 matching upstream cryptographic hashes.
• The RomFS/data directory contains build_manifest.psv and the required 18 .data archives.

Your original files are opened strictly in read-only mode and are never modified or moved.

Step 4: Prepare the Local Environment

The assistant eliminates manual Python, CMake, and LLVM installations:

1. Review the required dependencies and check the confirmation box authorizing downloads from official endpoints.
2. Click Prepare Environment.
3. The assistant automatically downloads and unpacks into an isolated local directory (%LOCALAPPDATA%\D2RPrepAssistant):
4. Portable Python 3.12 runtime and five cryptographic-hash-locked wheels.
5. Microsoft .NET SDK 10 (used for the upstream shader compiler).
6. Windows LLVM-MinGW toolchain (clang, clang++, lld).
7. Pinned SPIRV-Cross source archive (vulkan-sdk-1.4.357.0) and compiles spirv-cross.exe locally using two threads.
8. This process does not alter your Windows registry or global system PATH. All environment variables remain sandboxed inside the assistant’s child processes.

Step 5: Run Verification & Package IPA

1. Click Run Checks to confirm all tools and game input files are in place.
2. Click Start Preparation.
3. The assistant creates an isolated scratch workspace, copies necessary files, rewrites executable symbols into an iOS-compatible dynamic library, and translates Vulkan shaders to Apple Metal Shading Language (MSL) source text.
4. You can cancel the operation at any time. Cancelling automatically cleans up temporary scratch files while preserving cached portable toolchains for future runs.
5. Upon successful exit (status 0), the assistant publishes the verified, uniquely named .ipa to your designated output directory and displays its SHA-256 digest.

Step 6: Sideloading & Resource Transfer

The generated .ipa is an unsigned binary package that excludes the multi-gigabyte .data resource archives. To play on your device:

1. Sign and Sideload: Use an independent signing utility like Sideloadly to install the .ipa onto your iPhone or iPad using your personal Apple ID.
2. Transfer Game Resources: Connect your device to a computer and copy the 18 .data archives into the application's document folder using iTunes File Sharing or Finder.
3. First-Launch Shader Compilation: On first startup, the application compiles the translated MSL shaders on-device. Upstream reports around seven minutes on an iPhone 17 Pro Max; this is not a benchmark of this assistant or a guarantee for your device. Keep the app foregrounded during initial preparation.

Early Access Status & Test Boundary

We believe in honest, transparent technical documentation:

• What has been tested: Windows portable toolchain preparation, private-cache reuse, packaged Electron UI tests, and real source / clean-shell network downloads with hash checks passed. The final Windows regression run had 40 passes, 0 failures and 1 explicit platform skip; Linux had 41 passes with no skips. Full cold-network SDK preparation was not tested end to end.
• What has not been tested: End-to-end game packaging using proprietary game files and subsequent physical on-device installation/execution on an iPhone or iPad have not been tested on a physical device by this project.
• No one-click guarantee: Because iOS sideloading, weekly certificate refreshes, and separate resource transfers remain manual player responsibilities, we do not claim "one-click playability".

If you encounter issues or wish to inspect the engine code, visit the D2R Prep Assistant GitHub repository.

Feedback & Experience Reports (留言建议)

Encountered an issue running the assistant, have toolchain suggestions, or verified a successful package build on your Windows setup? Share your experience anonymously on our Feedback & Suggestions (留言建议) page. All feedback is reviewed by the maintainer before publication.