diff --git a/GeoModelIO/CMakeLists.txt b/GeoModelIO/CMakeLists.txt
index e30e0fe2c63c4b66b647602f4cbdd8356fe731cd..cf8bda02f157fa7033637b841de3a9a1bba6f25f 100644
--- a/GeoModelIO/CMakeLists.txt
+++ b/GeoModelIO/CMakeLists.txt
@@ -9,7 +9,7 @@ add_subdirectory( GeoModelDBManager )
add_subdirectory( TFPersistification )
add_subdirectory( GeoModelRead )
add_subdirectory( GeoModelWrite )
-# add_subdirectory( GeoModelIOHelpers )
+add_subdirectory( GeoModelIOHelpers )
add_subdirectory( GeoModelCppHelpers )
# Create and install the version description of the project.
@@ -47,3 +47,10 @@ install(
# Set up the packaging of the project using CPack.
list( APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake )
include( GeoModelIOPackaging )
+
+# global I/O tests
+add_executable(test_io_shared_serialtransformers tests/test_io_shared_serialtransformers.cpp)
+target_link_libraries( test_io_shared_serialtransformers GeoModelIO::GeoModelDBManager GeoModelCore::GeoModelHelpers GeoModelCore::GeoModelKernel GeoModelIO::GeoModelIOHelpers)
+add_test(NAME testIOSharedSerialTransformers
+ COMMAND test_io_shared_serialtransformers)
+
diff --git a/GeoModelIO/GeoModelDBManager/CMakeLists.txt b/GeoModelIO/GeoModelDBManager/CMakeLists.txt
index 1d7c55f26968a60711c237a3138488dc6b6543f9..91182b1a7b2680d614bd2119ee52f70f513b6e15 100644
--- a/GeoModelIO/GeoModelDBManager/CMakeLists.txt
+++ b/GeoModelIO/GeoModelDBManager/CMakeLists.txt
@@ -41,5 +41,5 @@ install( FILES ${HEADERS}
add_executable(test_create_db_file tests/test_create_db_file.cpp)
target_link_libraries( test_create_db_file GeoModelIO::GeoModelDBManager)
-add_test(NAME TestCreateDBFile
+add_test(NAME testCreateDBFile
COMMAND test_create_db_file)
diff --git a/GeoModelIO/tests/test_io_shared_serialtransformers.cpp b/GeoModelIO/tests/test_io_shared_serialtransformers.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..bc0bbbbf390f743dd443f2b3311c422f1f978f63
--- /dev/null
+++ b/GeoModelIO/tests/test_io_shared_serialtransformers.cpp
@@ -0,0 +1,168 @@
+// Copyright (C) 2002-2024 CERN for the benefit of the ATLAS collaboration
+
+/*
+ * This example tests shared GeoSerialTransformer and Function nodes.
+ *
+ * It creates one single LogVol, with one Material and one Shape.
+ * Then it creates one single PhysVol volumes using the above LogVol.
+ * Then it creates two SerialTrasnformers with two different placing formulas,
+ * but which share the same PhysVol defined above.
+ *
+ * It is meant to how how to share GeoModel nodes to reduce the memory footprint
+ * and to test the GeoModel I/O packages and methods.
+ *
+ * Author: Riccardo Maria BIANCHI @ CERN
+ * Created on: Apr, 2024
+ *
+ */
+
+
+// GeoModel includes
+#include "GeoGenericFunctions/AbsFunction.h"
+#include "GeoGenericFunctions/Cos.h"
+#include "GeoGenericFunctions/Sin.h"
+#include "GeoGenericFunctions/Variable.h"
+#include "GeoModelDBManager/GMDBManager.h"
+#include "GeoModelIOHelpers/GMIO.h"
+#include "GeoModelIOHelpers/GMTests_IO.h"
+#include "GeoModelKernel/GeoBox.h"
+#include "GeoModelKernel/GeoFullPhysVol.h"
+#include "GeoModelKernel/GeoPhysVol.h"
+#include "GeoModelKernel/GeoSerialDenominator.h"
+#include "GeoModelKernel/GeoSerialTransformer.h"
+#include "GeoModelKernel/GeoTube.h"
+#include "GeoModelHelpers/defineWorld.h"
+
+// C++ includes
+#include <cstdlib> // EXIT_FAILURE
+#include <fstream>
+#include <iostream>
+
+// Units
+#include "GeoModelKernel/Units.h"
+#define SYSTEM_OF_UNITS \
+ GeoModelKernelUnits // so we will get, e.g., 'GeoModelKernelUnits::cm'
+
+using namespace GeoGenfun;
+using namespace GeoXF;
+
+int main(int argc, char *argv[]) {
+// Define the units
+#define gr SYSTEM_OF_UNITS::gram
+#define mole SYSTEM_OF_UNITS::mole
+#define cm3 SYSTEM_OF_UNITS::cm3
+#define degree SYSTEM_OF_UNITS::degree
+
+ // get the World volume,
+ // we build it outside the class for convenience only
+ GeoIntrusivePtr<GeoPhysVol> world{createGeoWorld()};
+
+ // Define elements used in this example:
+ GeoElement *aluminum = new GeoElement("Aluminum", "Al", 13, 26 * gr / mole);
+ GeoElement *iron = new GeoElement("Iron", "Fe", 26.0, 55.847 * gr / mole);
+
+ // Define materials:
+ double densityOfAluminum = 2.7; // g/cm^3
+ double densityOfIron = 7.87; // g/cm^3
+ GeoMaterial *Aluminum = new GeoMaterial("Aluminum", densityOfAluminum);
+ Aluminum->add(aluminum, 1.0);
+ Aluminum->lock();
+ GeoMaterial *Iron = new GeoMaterial("Iron", densityOfIron);
+ Iron->add(iron, 1.0);
+ Iron->lock();
+
+ // define a container box
+ const GeoBox *toyBox =
+ new GeoBox(1200 * SYSTEM_OF_UNITS::cm, 1200 * SYSTEM_OF_UNITS::cm,
+ 1200 * SYSTEM_OF_UNITS::cm);
+ const GeoLogVol *toyLog = new GeoLogVol("ToyLog", toyBox, Aluminum); //
+ GeoPhysVol *toyPhys = new GeoPhysVol(toyLog);
+
+ //--------------------------------------//
+ // Define some daughters and put them in the toy volume
+ //--------------------------------------//
+ const GeoTube *ringTube =
+ new GeoTube(500 * SYSTEM_OF_UNITS::cm, 1000 * SYSTEM_OF_UNITS::cm,
+ 5.0 * SYSTEM_OF_UNITS::cm);
+ const GeoLogVol *ringLog = new GeoLogVol("RingLog", ringTube, Aluminum);
+ // define a global name for the daughters
+ GeoSerialDenominator *ringName = new GeoSerialDenominator("RING");
+ toyPhys->add(ringName);
+ // Make 100 of these //
+ // within the volume of the toy: //
+ for (int i = 0; i < 100; i++) {
+ GeoFullPhysVol *ringPhys = new GeoFullPhysVol(ringLog);
+ GeoAlignableTransform *xform = new GeoAlignableTransform(
+ GeoTrf::TranslateZ3D((i - 50) * 20 * SYSTEM_OF_UNITS::cm));
+ toyPhys->add(xform);
+ toyPhys->add(ringPhys);
+ }
+
+ //--------------------------------------//
+ // Now, in addition to active daughters,
+ // add some passive material.
+ // This is done here using
+ // the "SerialTransformer",
+ // our way of parameterizing volumes.
+ // It does not need to be done this way,
+ // but we want to provide an example of
+ // parametrizations in the Toy
+ //--------------------------------------//
+
+ GeoBox *sPass =
+ new GeoBox(5.0 * SYSTEM_OF_UNITS::cm, 30 * SYSTEM_OF_UNITS::cm,
+ 30 * SYSTEM_OF_UNITS::cm);
+ GeoLogVol *lPass = new GeoLogVol("Passive", sPass, Iron);
+ GeoPhysVol *pPass = new GeoPhysVol(lPass);
+
+ //--------------------------------------//
+ // Now, define two mathematical functions,
+ // which are used to parametrically place the volumes
+ // in space.
+ //--------------------------------------//
+ const unsigned int NPLATES = 100;
+ Variable i;
+ Sin sin;
+ GENFUNCTION f = 360 * SYSTEM_OF_UNITS::deg / NPLATES * i;
+ GENFUNCTION g = sin(4 * f);
+ GENFUNCTION h = -g;
+ TRANSFUNCTION t1 = Pow(GeoTrf::RotateZ3D(1.0), f) *
+ GeoTrf::TranslateX3D(1100 * SYSTEM_OF_UNITS::cm) *
+ Pow(GeoTrf::TranslateZ3D(800 * SYSTEM_OF_UNITS::cm), g);
+ TRANSFUNCTION t2 = Pow(GeoTrf::RotateZ3D(1.0), f) *
+ GeoTrf::TranslateX3D(1100 * SYSTEM_OF_UNITS::cm) *
+ Pow(GeoTrf::TranslateZ3D(800 * SYSTEM_OF_UNITS::cm), h);
+
+ //--------------------------------------//
+ // Inside, by the way, the serial transformer
+ // will evaluate the functions:
+ // HepTransform3D xf = t1(i), for i=1,NPLATES....
+ //--------------------------------------//
+
+ GeoSerialDenominator *pass1Name = new GeoSerialDenominator("PASSIVE-1-");
+ GeoSerialTransformer *s1 = new GeoSerialTransformer(pPass, &t1, NPLATES);
+ toyPhys->add(pass1Name);
+ toyPhys->add(s1);
+
+ GeoSerialDenominator *pass2Name = new GeoSerialDenominator("PASSIVE-2-");
+ GeoSerialTransformer *s2 = new GeoSerialTransformer(pPass, &t2, NPLATES);
+ toyPhys->add(pass2Name);
+ toyPhys->add(s2);
+
+ world->add(toyPhys);
+
+ // --- I/O TESTS ---
+ std::cout << "\nTests:\n";
+ unsigned loglevel = 3;
+ unsigned printtests = 1;
+ const bool forceDelete = true;
+ std::pair<bool, std::map<std::string, bool>> tests =
+ GeoModelIO::TestIO::runAllTests(world, loglevel, printtests, forceDelete);
+ bool testall = tests.first;
+
+ // Return 0 if all OK! :-)
+ // Return 1 otherwise... :-(
+ if (testall) return 0;
+ return 1;
+ // ----------------
+}