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GAMMA Easy

A small Windows installer and launcher for S.T.A.L.K.E.R. Anomaly + GAMMA. Choose an internal drive, let it handle the downloads and setup, then launch the game through Mod Organizer 2.

Early alpha: 36 isolated checks passed, and the first real installation reached the game world, confirmed by the user on 2026-10-09. Extended gameplay and other Windows configurations still need testing. See validation status. This project is independent of GAMMA, GSC Game World, and the installer backend's authors.

What it handles

• A drive picker that follows the folder rules. Creates D:\Anomaly and D:\GAMMA at the selected drive's root; checks NTFS, internal drives, and space.
• Downloads and setup. Uses the pinned FaithBeam installer to acquire Anomaly, GAMMA components, and mods from their upstream sources and configure MO2.
• Stop and retry. Keeps complete downloaded archives and stops backend child processes. A partial individual download may restart.
• Required Microsoft components. Downloads Visual C++ and DirectX from Microsoft, verifies their signatures, and handles restart requirements.
• An explicit Defender option. Folder exclusions are optional; antivirus is never disabled.
• Play through MO2. Checks the installed profile, DX11 entry, required files, and enabled mod folders before allowing launch.
• Optional xrRazom co-op. Package verification, a separate profile, reversible engines, recovery and read-only friend comparison. Two-player gameplay needs validation. Co-op guide.

The setup contains the launcher and installer engine. It does not bundle game files or the modpack. An existing installation is not imported or overwritten.

Get started

1. Open Releases and download the Windows x64 package.
2. Extract the package, run GammaSetup.exe, and click Install launcher.
3. Choose an internal NTFS drive with about 200 GB free and click Install.
4. Accept the Windows administrator prompt. When the checks finish, click Play.

Requirement	Supported
Windows	Windows 10/11, x64
Launcher runtime	.NET Framework 4.8
Game location	Internal NTFS drive; SSD preferred
Fresh-install space	About 200 GB free
Connection	Internet access to the upstream download providers

Windows 7, ARM64, USB drives, and existing manual installations are not supported by this build. The executable is unsigned. Read the installation guide before testing it.

Build from source

On Windows x64, open PowerShell in the repository:

.\scripts\build.ps1
.\scripts\test.ps1

The build fetches a version-pinned, SHA256-checked installer backend and embeds it in build\GammaSetup.exe. It uses the .NET Framework compiler supplied with Windows; no NuGet restore or developer SDK is required for this wrapper.

To assemble an installer ZIP and corresponding source bundle:

.\scripts\package.ps1

See development for the layout, dependency locks, and release workflow. CI builds and tests the wrapper without downloading the game or installing Microsoft runtimes.

Known limits

• The first installation reached the world; extended gameplay and additional machines still need testing.
• Download hosts can fail, throttle, or present bot challenges.
• Retry reuses verified complete archives; universal byte-level resume is not implemented.
• Repair / update reapplies the official GAMMA profile and can reset custom mod selections and executable entries. The backend is asked to preserve user.ltx and MCM settings.
• The current UI uses the backend's per-item log and an activity indicator rather than a single overall download percentage.
• The launcher has no automatic self-update or Windows uninstall registration yet.

Follow the roadmap, or report a reproducible problem.

Experimental co-op: 0.2.0 adds xrRazom setup and switching. Setup stays optional and inactive until Co-op is selected. The candidate comparison also covers Anomaly Together 2 and improvements to mode switching, friend compatibility, and recovery.

Credits and license

• Grokitach / STALKER GAMMA: modpack, definitions, and installation documentation.
• FaithBeam / stalker-gamma-cli: the installation engine. This project builds a Windows GUI around that work.
• The Anomaly team, Mod Organizer 2 contributors, 7-Zip, and the mod authors.
• GSC Game World: the S.T.A.L.K.E.R. universe.

GAMMA Easy is GPL-3.0-or-later. The backend and native components retain their own licenses. See LICENSE and third-party notices. Release source bundles include the matching backend and native dependency sources.