diff --git a/src/cpp/helpers/ArchiveIO.h b/src/cpp/helpers/ArchiveIO.h
index b97666ecdc..00805d9acb 100644
--- a/src/cpp/helpers/ArchiveIO.h
+++ b/src/cpp/helpers/ArchiveIO.h
@@ -27,11 +27,14 @@ class ArchiveIOSpecificException : public std::runtime_error {
             std::to_string(expectedStatus) + " expected)") {}
 };
 #include <filesystem>
+#include <shared_mutex>
 class ArchiveIO {
  private:
   std::filesystem::path archivePath_;
 
  protected:
+  mutable std::shared_mutex mutex_;
+
   virtual void Create() = 0;
 
  public:
diff --git a/src/cpp/helpers/ArchiveReader.cpp b/src/cpp/helpers/ArchiveReader.cpp
index f06f12cdb1..cdfc1515ee 100644
--- a/src/cpp/helpers/ArchiveReader.cpp
+++ b/src/cpp/helpers/ArchiveReader.cpp
@@ -34,6 +34,7 @@ int32_t ArchiveReader::ExtractFile(
 int32_t ArchiveReader::ExtractFile(
     const std::filesystem::path& fileToExtractPath,
     const std::filesystem::path& destination) {
+  std::unique_lock lock(mutex_);
   int32_t err = MZ_OK;
   LocateEntry(fileToExtractPath);
   OpenEntry(fileToExtractPath);
@@ -74,6 +75,7 @@ void ArchiveReader::OpenEntry(const std::filesystem::path& fileToExtractPath) {
 }
 std::istringstream ArchiveReader::ExtractFileInStringStream(
     const std::filesystem::path& FileToExtractPath) {
+  std::unique_lock lock(mutex_);
   LocateEntry(FileToExtractPath);
   OpenEntry(FileToExtractPath);
   int32_t len = mz_zip_reader_entry_save_buffer_length(internalPointer_);
diff --git a/src/cpp/helpers/ArchiveWriter.cpp b/src/cpp/helpers/ArchiveWriter.cpp
index 9c0ca3fe0f..712f9b5bfc 100644
--- a/src/cpp/helpers/ArchiveWriter.cpp
+++ b/src/cpp/helpers/ArchiveWriter.cpp
@@ -39,6 +39,7 @@ int32_t ArchiveWriter::Close() { return mz_zip_writer_close(internalPointer_); }
 void ArchiveWriter::Delete() { mz_zip_writer_delete(&internalPointer_); }
 
 int32_t ArchiveWriter::AddFileInArchive(const FileBuffer& FileBufferToAdd) {
+  std::unique_lock lock(mutex_);
   fileInfo_.filename = FileBufferToAdd.fname.c_str();
   fileInfo_.creation_date = std::time(0);
   int32_t err = mz_zip_writer_entry_open(internalPointer_, &fileInfo_);
@@ -75,6 +76,7 @@ int32_t ArchiveWriter::AddFileInArchive(const FileBuffer& FileBufferToAdd) {
 }
 int32_t ArchiveWriter::AddFileInArchive(
     const std::filesystem::path& FileToAdd) {
+  std::unique_lock lock(mutex_);
   auto err =
       mz_zip_writer_add_file(internalPointer_, FileToAdd.string().c_str(),
                              FileToAdd.filename().string().c_str());
diff --git a/src/cpp/lpnamer/problem_modifier/LinkProblemsGenerator.cpp b/src/cpp/lpnamer/problem_modifier/LinkProblemsGenerator.cpp
index ca2f2d67e6..8e88abe1d5 100644
--- a/src/cpp/lpnamer/problem_modifier/LinkProblemsGenerator.cpp
+++ b/src/cpp/lpnamer/problem_modifier/LinkProblemsGenerator.cpp
@@ -129,9 +129,9 @@ void LinkProblemsGenerator::treatloop(const std::filesystem::path &root,
   auto writer = ArchiveWriter(tmpArchivePath);
   writer.Open();
   auto mpsList = readMPSList(mps_file_name);
-  std::for_each(std::execution::seq, mpsList.begin(), mpsList.end(), [&](const auto& mps) {
-    treat(root, mps, couplings, reader, writer);
-  });
+  std::for_each(
+      std::execution::par, mpsList.begin(), mpsList.end(),
+      [&](const auto &mps) { treat(root, mps, couplings, reader, writer); });
   reader.Close();
   reader.Delete();
   writer.Close();