diff --git a/Compiler/geant4/build b/Compiler/geant4/build
new file mode 100755
index 0000000..68cb0f4
--- /dev/null
+++ b/Compiler/geant4/build
@@ -0,0 +1,25 @@
+#!/usr/bin/env modbuild
+
+pbuild::set_download_url "http://cern.ch/geant4-data/releases/$P.${V_PKG}.tar.gz"
+pbuild::add_to_group 'Compiler'
+
+#pbuild::install_docfiles 'ChangeLog'
+#pbuild::install_docfiles 'compilers.txt'
+#pbuild::install_docfiles 'COPYING'
+#pbuild::install_docfiles 'COPYING.LESSER'
+#pbuild::install_docfiles 'README.md'
+
+pbuild::pre_configure() {
+	pbuild::add_configure_args "-DCMAKE_INSTALL_PREFIX=${PREFIX}"
+	pbuild::add_configure_args "-DGEANT4_USE_SYSTEM_CLHEP=ON"
+	pbuild::add_configure_args "-DPC_EXPAT_INCLUDE_DIRS=${LIBEXPAT_INCLUDE_DIR}"
+	if pbuild::use_flag 'multithreaded'; then
+		pbuild::add_configure_args "-DGEANT4_BUILD_MULTITHREADED=ON"
+	fi
+}
+
+# Local Variables:
+# mode: sh
+# sh-basic-offset: 8
+# tab-width: 8
+# End:
diff --git a/Compiler/geant4/files/variants b/Compiler/geant4/files/variants
new file mode 100644
index 0000000..92ed55b
--- /dev/null
+++ b/Compiler/geant4/files/variants
@@ -0,0 +1 @@
+geant4/10.05	unstable	gcc/7.3.0 clhep/2.4.1.0 b:libexpat/2.2.6 b:cmake/3.9.6
diff --git a/Compiler/geant4/modulefile b/Compiler/geant4/modulefile
new file mode 100644
index 0000000..922546c
--- /dev/null
+++ b/Compiler/geant4/modulefile
@@ -0,0 +1,13 @@
+#%Module1.0
+
+module-whatis		"class library for high energy physics"
+module-url		"https://proj-clhep.web.cern.ch/proj-clhep/"
+module-license		"GNU GPL, GNU GLPL"
+module-maintainer	"Achim Gsell <achim.gsell@psi.ch>"
+module-help 		"
+The CLHEP project was proposed by Leif Lönnblad at CHEP 92. It is intended
+to be a set of HEP-specific foundation and utility classes such as random
+generators, physics vectors, geometry and linear algebra. CLHEP is structured
+in a set of packages independent of any external package (interdependencies
+within CLHEP are allowed under certain conditions). 
+"