GregTools Modmanager

Desktop app for Steam Workshop management, mod browsing, and publishing for Data Center (Steamworks API, App ID 4170200).

📦 Open-source and external dependencies

This project is developed in the open and uses many open-source libraries (.NET, MAUI, Facepunch.Steamworks, and more). It also ships Valve’s closed-source steam_api64.dll (Steamworks), which is governed by Valve terms.

See EXTERNAL_DEPENDENCIES.md for a full license and redistribution breakdown.

✨ Features

• Mod Store: Browse, search, subscribe, favorite, and vote on Workshop items.
• Mod Manager: Dependency health checks, MelonLoader status, and FMF plugin channels.
• Authoring tools: Create projects from templates, edit metadata, and publish with change notes.
• Template scaffolding: Modded templates create content/Mods, content/Plugins, and content/ModFramework/ (including ModFramework/FMF/Plugins) to mirror {GameRoot} layout.
• Post-upload sync: Re-downloads from Steam after publish to keep local content in sync.
• Headless CLI: Supports scripted/CI publish flows.
• Pagination: All major list views support paging.

🧰 Open in Visual Studio

Use WorkshopUploader.sln in this repository root.

If you open only WorkshopUploader.csproj from another solution context, Visual Studio may pick a different solution unexpectedly.

🏗️ Build

dotnet build WorkshopUploader.csproj -c Debug

Or:

dotnet build WorkshopUploader.sln -c Debug

Target: .NET 9 + .NET MAUI (Windows). The project uses WindowsAppSDKSelfContained so required Windows App SDK components are shipped with the app.

▶️ Run (recommended)

• Use Visual Studio 2022 with the .NET MAUI workload and Windows App SDK components.
• Open WorkshopUploader.sln.
• Set WorkshopUploader as startup project.
• Press F5.

📤 Publish (win10-x64)

dotnet publish WorkshopUploader.csproj -c Release

Output:

bin/Release/net9.0-windows10.0.19041.0/win10-x64/publish/WorkshopUploader.exe

Publish to a custom self-contained folder

dotnet publish WorkshopUploader.csproj -c Release -p:SelfContained=true -p:WindowsPackageType=None -p:WindowsAppSDKSelfContained=true -o .\publish-out

🧱 Create installer (Setup.exe via Inno Setup)

1. Install Inno Setup 6 (includes ISCC.exe).
2. Run:

.\build.ps1

This runs dotnet publish and creates:

installer\Output\GregToolsModmanager-<Version>-Setup.exe

Installer behavior:

• Wizard install/uninstall integration in Windows Apps settings.
• Start menu entry and optional desktop shortcut.
• Default install path: C:\Program Files\GregTools Modmanager (admin required).

Useful options:

• Skip publish and only rebuild setup: ./build.ps1 -SkipPublish
• Inno script path: installer\GregToolsModmanager.iss

Update/reinstall behavior

• Setup uses the same AppId, detects existing installs, and overwrites the target folder.
• Running WorkshopUploader.exe is closed through Windows Restart Manager (CloseApplications).
• Portable install via install-local.ps1 also closes the app and replaces the install directory.

App does not start after setup

• The installer runs elevated, but final launch uses runasoriginaluser so the app starts non-elevated (important for WinUI/WebView2/MAUI stability).
• If problems continue, check Event Viewer and test CloseApplications=no in GregToolsModmanager.iss.

🔐 Code signing, SmartScreen, and trust notice

• Current state: We currently use self-signed code signing for CI/community builds.
• Why: I cannot afford an official OV/EV certificate at the moment.
• Impact for users: Windows/SmartScreen may still show warnings (for example, Unknown Publisher or reputation prompts), even when the file is signed.
• Runtime note: This app targets .NET 9 + .NET MAUI (Windows) and depends on Windows runtime components; if startup fails on end-user systems, install/repair the Visual C++ Redistributable and Windows App SDK runtime (see troubleshooting below).
• Rotation policy: CI rotates/recreates self-signed certificates on a 7-day cadence (or earlier if close to expiry), and refreshes the rolling latest prerelease artifacts after successful signing.

Signing commands and references

• Official OV/EV code signing is currently not enabled due to certificate cost.
• A self-signed CI path is available for community/testing builds.
• Manual signing docs: installer\CODE_SIGNING.md.
• Create a self-signed certificate:

.\installer\create-selfsigned-codesign-cert.ps1

• Sign only (without rebuilding setup):

.\build.ps1 -SignOnly

Set CODE_SIGN_THUMBPRINT (or use -SetupPath when needed).

💼 Portable install (no Setup.exe)

.\install-local.ps1

Installs per-user to %LOCALAPPDATA%\Programs\GregTools Modmanager\ (no admin).

Uninstall:

.\install-local.ps1 -Uninstall

🧯 Crash dumps (WER LocalDumps)

Enable local dumps:

.\installer\configure-localdumps.ps1

Enable machine-wide (elevated shell):

.\installer\configure-localdumps.ps1 -Scope Machine

Disable:

.\installer\configure-localdumps.ps1 -Disable

Default dump directories:

• Current user: %LOCALAPPDATA%\GregToolsModmanager\dumps
• Machine: C:\ProgramData\GregToolsModmanager\dumps

🚚 Deploy all mods to Workshop folders

pwsh -File scripts/Deploy-Release-ToWorkshop.ps1

Builds framework/plugins/mods and creates Steamworks-compatible project folders under <GameRoot>/workshop/.

🩺 Troubleshooting

1. Open Event Viewer → Windows Logs → Application and look for WorkshopUploader.exe faults.
2. Install/repair the Microsoft Visual C++ Redistributable.
3. Install the Windows App SDK Runtime.
4. Prefer running with F5 from Visual Studio on the same machine you use to build.
5. Ensure Windows 10 version 1809+ (OS build 17763+).

🎮 Deploy next to the game

Copy the publish output to:

{GameRoot}/WorkshopUploader/

Place it next to the game executable (not inside Mods or MelonLoader).

🛡️ VirusTotal

Third-party scan for transparency (self-contained .NET apps may be flagged heuristically; always compare checksums from official releases):

• SHA-256: c0ea7929eee9d754e81363e9ec81c601e763e65f7db1eb0d971edf2c2036f0af
• Report: VirusTotal file relations

❤️ Sponsorship

If this project helps you and you want to support ongoing maintenance and improvements:

• Sponsor: github.com/sponsors/mleem97

🔗 See also

• External dependencies and distribution notes
• Workshop wiki page
• End-user guide
• Contributor guide