g4install

Environment modules, installation scripts, container images, and CVMFS distribution for Geant4 — with seamless coexistence of multiple Geant4 versions.

This repository provides:

• Environment Modules + installation scripts for Geant4
• Multi-architecture Docker images vi CI(amd64, arm64)

Why use g4install?

g4install is designed to let you:

• Install multiple Geant4 versions side-by-side
• Switch between versions quickly using module load / module switch
• Automatically install and load required dependencies (CLHEP, Xerces-C)
• Easy, consistent, shell independent environment

This is especially useful:

• one reliable command to install the latest or past Geant4 versions and its dependencies
• validating applications against different Geant4 releases (e.g. 11.3.x vs 11.4.x)

Quick Start (Local Installation)

Prerequisites

Install Environment Modules:

• Linux: install environment-modules using your package manager
• macOS: brew install modules

1. Clone and enable g4install modules

Here we use /path/to/g4install as an example.

git clone https://github.com/gemc/g4install
module use /path/to/g4install

We recommend adding the module use command to your shell init script, like .bashrc or .cshrc.

You can now list supported Geant4 versions:

module avail geant4

2. Install a Geant4 version (example: 11.4.1 )

module load sim_system
install_geant4 11.4.1

3. Load a Geant4 version

module load geant4/11.4.1

To verify an active version

geant4-config --version
which geant4-config

Seamless Multi-Version Switching

One of the main features of g4install is the ability to keep multiple versions installed and switch between them without conflicts.

module load geant4/11.3.2
# build/test project A

module switch geant4/11.4.1
# build/test project B

Docker Images

Images are built by CI and published to the G4Install GitHub Container Registry.

Highlights

• Multi-arch tags (same tag works on Intel and Apple Silicon)
• Batch mode and GUI mode (VNC / noVNC)
• Includes Geant4 and ROOT

Batch mode example

docker run --rm -it ghcr.io/gemc/g4install:11.4.0-ubuntu-24.04 bash -li

GUI mode example (VNC / noVNC)

VPORTS=(-p 6080:6080 -p 5900:5900)
VNC_PASS=(-e X11VNC_PASSWORD=change-me)
VNC_BIND=(-e VNC_BIND=0.0.0.0)
GEO_FLAGS=(-e GEOMETRY=1920x1200)

docker run --rm -it $VPORTS $VNC_BIND $VNC_PASS $GEO_FLAGS ghcr.io/gemc/g4install:11.4.0-ubuntu-24.04

Supported Images (current examples)

Latest Geant4 (11.4.1)

OS	Pull Command	arm64	amd64
ubuntu 24.04	docker pull ghcr.io/gemc/g4install:11.4.1-ubuntu24	yes	yes
fedora 42	docker pull ghcr.io/gemc/g4install:11.4.1-fedora42	yes	yes
almalinux 9.4	docker pull ghcr.io/gemc/g4install:11.4.1-almalinux9.4	yes	yes
debian 13	docker pull ghcr.io/gemc/g4install:11.4.1-debian-13	yes	yes
archlinux latest	docker pull ghcr.io/gemc/g4install:11.4.1-archlinux-latest	no	yes

To list all suported version check the github registry for g4install

Troubleshooting

module: command not found

Environment Modules is not installed or not initialized in the current shell.

• Install environment-modules (Linux) or modules (macOS/Homebrew)
• Start a login shell or source your shell initialization files

module avail geant4 shows nothing

Confirm the repository is added to the module search path:

module use /path/to/g4install

The wrong Geant4 version is being picked up

Check current shell state:

module list
which geant4-config
geant4-config --version

If needed:

module purge
module use /path/to/g4install
module load geant4/<desired-version>

CI Status