diff --git a/src/cpp/helpers/CMakeLists.txt b/src/cpp/helpers/CMakeLists.txt
index 322be120e..28abc5a3e 100644
--- a/src/cpp/helpers/CMakeLists.txt
+++ b/src/cpp/helpers/CMakeLists.txt
@@ -23,7 +23,6 @@ target_sources(helpers PRIVATE
         ${CMAKE_CURRENT_SOURCE_DIR}/ArchiveWriter.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/Clock.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/FileInBuffer.cpp
-        ${CMAKE_CURRENT_SOURCE_DIR}/JsonXpansionReader.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/OptionsParser.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/helpers/AntaresArchiveUpdater.h
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/helpers/AntaresArchiveUpdaterExeOptions.h
diff --git a/src/cpp/study-updater/CMakeLists.txt b/src/cpp/study-updater/CMakeLists.txt
index 3f729950e..15171a608 100644
--- a/src/cpp/study-updater/CMakeLists.txt
+++ b/src/cpp/study-updater/CMakeLists.txt
@@ -1,19 +1,21 @@
 add_library(xpansion_study_updater_lib)
 target_sources(xpansion_study_updater_lib PRIVATE
+        ${CMAKE_CURRENT_SOURCE_DIR}/JsonXpansionReader.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/LinkCapacitiesCSVWriter.cpp
-        ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdateStrategy.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/LinkParametersCSVOverwriter.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdateLinkCapacitiesStrategy.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdateLinkParameterStrategy.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdateRunner.cpp
-        ${CMAKE_CURRENT_SOURCE_DIR}/LinkParametersCSVOverwriter.cpp
+        ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdateStrategy.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/StudyUpdater.cpp
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/LinkCapacitiesCSVWriter.h
-        ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdateStrategy.h
+        ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/LinkParametersCSVOverwriter.h
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdateLinkCapacitiesStrategy.h
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdateLinkParameterStrategy.h
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdateRunner.h
-        ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/LinkParametersCSVOverwriter.h
+        ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdateStrategy.h
         ${CMAKE_CURRENT_SOURCE_DIR}/include/antares-xpansion/study-updater/StudyUpdater.h
+        ${CMAKE_CURRENT_SOURCE_DIR}/private/JsonXpansionReader.h
 )
 
 target_link_libraries(xpansion_study_updater_lib
@@ -29,6 +31,8 @@ target_link_libraries(xpansion_study_updater_lib
 target_include_directories(xpansion_study_updater_lib
         PUBLIC
         $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
+        PRIVATE
+        $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/private>
 )
 
 add_library(${PROJECT_NAME}::xpansion_study_updater_lib ALIAS xpansion_study_updater_lib)
diff --git a/src/cpp/helpers/JsonXpansionReader.cpp b/src/cpp/study-updater/JsonXpansionReader.cpp
similarity index 95%
rename from src/cpp/helpers/JsonXpansionReader.cpp
rename to src/cpp/study-updater/JsonXpansionReader.cpp
index 6e252ab99..9acd49f0d 100644
--- a/src/cpp/helpers/JsonXpansionReader.cpp
+++ b/src/cpp/study-updater/JsonXpansionReader.cpp
@@ -1,4 +1,4 @@
-#include "antares-xpansion/helpers/JsonXpansionReader.h"
+#include "JsonXpansionReader.h"
 
 #include <json/json.h>
 
diff --git a/src/cpp/study-updater/LinkParametersCSVOverwriter.cpp b/src/cpp/study-updater/LinkParametersCSVOverwriter.cpp
index cb23022e0..da4a66cf7 100644
--- a/src/cpp/study-updater/LinkParametersCSVOverwriter.cpp
+++ b/src/cpp/study-updater/LinkParametersCSVOverwriter.cpp
@@ -4,9 +4,8 @@
 
 #include "antares-xpansion/study-updater/LinkParametersCSVOverwriter.h"
 
-#include "antares-xpansion/helpers/JsonXpansionReader.h"
+#include "JsonXpansionReader.h"
 #include "antares-xpansion/lpnamer/problem_modifier/LinkdataRecord.h"
-#include "antares-xpansion/study-updater/StudyUpdater.h"
 
 bool LinkParametersCSVOverWriter::open(
     const std::filesystem::path& linkdataFilename_l) {
diff --git a/src/cpp/study-updater/StudyUpdater.cpp b/src/cpp/study-updater/StudyUpdater.cpp
index 9ace90821..dc9ea9180 100644
--- a/src/cpp/study-updater/StudyUpdater.cpp
+++ b/src/cpp/study-updater/StudyUpdater.cpp
@@ -2,7 +2,7 @@
 
 #include <utility>
 
-#include "antares-xpansion/helpers/JsonXpansionReader.h"
+#include "JsonXpansionReader.h"
 #include "antares-xpansion/study-updater/StudyUpdateLinkCapacitiesStrategy.h"
 #include "antares-xpansion/study-updater/StudyUpdateLinkParameterStrategy.h"
 #include "antares-xpansion/study-updater/StudyUpdateStrategy.h"
diff --git a/src/cpp/helpers/include/antares-xpansion/helpers/JsonXpansionReader.h b/src/cpp/study-updater/private/JsonXpansionReader.h
similarity index 100%
rename from src/cpp/helpers/include/antares-xpansion/helpers/JsonXpansionReader.h
rename to src/cpp/study-updater/private/JsonXpansionReader.h
diff --git a/tests/cpp/CMakeLists.txt b/tests/cpp/CMakeLists.txt
index 9f3f7f706..57c45ed00 100644
--- a/tests/cpp/CMakeLists.txt
+++ b/tests/cpp/CMakeLists.txt
@@ -32,3 +32,4 @@ add_subdirectory(zip_mps)
 add_subdirectory(benders)
 add_subdirectory(full_run)
 add_subdirectory(outer_loop)
+add_subdirectory(study_updater)
diff --git a/tests/cpp/helpers/CMakeLists.txt b/tests/cpp/helpers/CMakeLists.txt
index 587dbfa94..6574761c7 100644
--- a/tests/cpp/helpers/CMakeLists.txt
+++ b/tests/cpp/helpers/CMakeLists.txt
@@ -1,5 +1,4 @@
 add_executable (helpers_test
-		JsonXpansionReaderTest.cc
 		AntaresVersionProviderTest.cpp
 		OptionsParserTest.cpp)
 
@@ -18,7 +17,6 @@ target_link_libraries (helpers_test PRIVATE
 		antaresXpansion::lp_namer_model
 		antaresXpansion::lp_namer_input_reader
 		antaresXpansion::lp_namer_problem_modifier
-		${JSONCPP_LIB}
 		${PROJECT_NAME}::benders_sequential_core
 		)
 
diff --git a/tests/cpp/study_updater/CMakeLists.txt b/tests/cpp/study_updater/CMakeLists.txt
new file mode 100644
index 000000000..4deef589e
--- /dev/null
+++ b/tests/cpp/study_updater/CMakeLists.txt
@@ -0,0 +1,22 @@
+add_executable(study_updater_test)
+target_sources(study_updater_test PRIVATE
+        JsonXpansionReaderTest.cc
+)
+
+# Get source dir to include private headers
+# Better way would be to rework test and use StudyUpdater::update as entry point
+get_target_property(STUDY_UPDATER_SOURCE_DIR ${PROJECT_NAME}::xpansion_study_updater_lib SOURCE_DIR)
+
+target_include_directories(study_updater_test
+PRIVATE
+        ${STUDY_UPDATER_SOURCE_DIR}/private # for private headers
+)
+
+target_link_libraries(study_updater_test
+        PRIVATE
+        ${PROJECT_NAME}::xpansion_study_updater_lib
+        ${JSONCPP_LIB}
+        GTest::Main
+)
+add_test(NAME study_updater_test COMMAND study_updater_test WORKING_DIRECTORY ${PROJECT_SOURCE_DIR})
+set_property(TEST study_updater_test PROPERTY LABELS unit)
diff --git a/tests/cpp/helpers/JsonXpansionReaderTest.cc b/tests/cpp/study_updater/JsonXpansionReaderTest.cc
similarity index 98%
rename from tests/cpp/helpers/JsonXpansionReaderTest.cc
rename to tests/cpp/study_updater/JsonXpansionReaderTest.cc
index 5408ff851..01fefc098 100644
--- a/tests/cpp/helpers/JsonXpansionReaderTest.cc
+++ b/tests/cpp/study_updater/JsonXpansionReaderTest.cc
@@ -1,7 +1,7 @@
 #include <fstream>
 #include <sstream>
 
-#include "antares-xpansion/helpers/JsonXpansionReader.h"
+#include "JsonXpansionReader.h"
 #include "gtest/gtest.h"
 
 class JsonXpansionReaderTest : public ::testing::Test {