diff --git a/src/libs/antares/study/area/links.cpp b/src/libs/antares/study/area/links.cpp
index ea7b8811f9..fa70cc855e 100644
--- a/src/libs/antares/study/area/links.cpp
+++ b/src/libs/antares/study/area/links.cpp
@@ -188,7 +188,7 @@ void AreaLink::storeTimeseriesNumbers(Solver::IResultWriter& writer) const
 
     std::string buffer;
     timeseriesNumbers.saveToBuffer(buffer);
-    writer.addEntryFromBuffer(path.string(), buffer);
+    writer.addEntryFromBuffer(path, buffer);
 }
 
 void AreaLink::detach()
diff --git a/src/libs/antares/study/area/store-timeseries-numbers.cpp b/src/libs/antares/study/area/store-timeseries-numbers.cpp
index 75d5f91896..daa3a250c8 100644
--- a/src/libs/antares/study/area/store-timeseries-numbers.cpp
+++ b/src/libs/antares/study/area/store-timeseries-numbers.cpp
@@ -40,7 +40,7 @@ static void storeTSnumbers(Solver::IResultWriter& writer,
     std::string buffer;
     timeseriesNumbers.saveToBuffer(buffer);
 
-    writer.addEntryFromBuffer(path.string(), buffer);
+    writer.addEntryFromBuffer(path, buffer);
 }
 
 void storeTimeseriesNumbersForLoad(Solver::IResultWriter& writer, const Area& area)
diff --git a/src/libs/antares/study/parts/common/cluster_list.cpp b/src/libs/antares/study/parts/common/cluster_list.cpp
index b8e16c5081..2551c507cf 100644
--- a/src/libs/antares/study/parts/common/cluster_list.cpp
+++ b/src/libs/antares/study/parts/common/cluster_list.cpp
@@ -28,7 +28,7 @@
 #include <antares/utils/utils.h>
 #include "antares/study/study.h"
 
-using namespace Yuni;
+namespace fs = std::filesystem;
 
 namespace Antares::Data
 {
@@ -88,21 +88,19 @@ void ClusterList<ClusterT>::resizeAllTimeseriesNumbers(uint n) const
     }
 }
 
-#define SEP IO::Separator
-
 template<class ClusterT>
 void ClusterList<ClusterT>::storeTimeseriesNumbers(Solver::IResultWriter& writer) const
 {
-    Clob path;
     std::string ts_content;
+    fs::path basePath = fs::path("ts-numbers") / typeID();
 
     for (auto& cluster: each_enabled())
     {
-        path.clear() << "ts-numbers" << SEP << typeID() << SEP << cluster->parentArea->id << SEP
-                     << cluster->id() << ".txt";
+        fs::path path = fs::path(cluster->parentArea->id) / std::string(cluster->id() + ".txt");
+
         ts_content.clear(); // We must clear ts_content here, since saveToBuffer does not do it.
         cluster->series.timeseriesNumbers.saveToBuffer(ts_content);
-        writer.addEntryFromBuffer(path.c_str(), ts_content);
+        writer.addEntryFromBuffer(path, ts_content);
     }
 }