diff --git a/src/files/files.cpp b/src/files/files.cpp
index 4c4d4ffd..3c0a7fe4 100644
--- a/src/files/files.cpp
+++ b/src/files/files.cpp
@@ -103,7 +103,7 @@ std::string files::read_string(const fs::path& filename) {
     return std::string((const char*)bytes.get(), size);
 }
 
-bool files::write_string(const fs::path& filename, const std::string content) {
+bool files::write_string(const fs::path& filename, const std::string& content) {
     std::ofstream file(filename);
     if (!file) {
         return false;
diff --git a/src/files/files.hpp b/src/files/files.hpp
index 1a124b25..5c3cd0b2 100644
--- a/src/files/files.hpp
+++ b/src/files/files.hpp
@@ -40,7 +40,7 @@ namespace files {
     uint append_bytes(const fs::path& file, const ubyte* data, size_t size);
 
     /// @brief Write string to the file
-    bool write_string(const fs::path& filename, const std::string content);
+    bool write_string(const fs::path& filename, const std::string& content);
 
     /// @brief Write dynamic data to the JSON file
     /// @param nice if true, human readable format will be used, otherwise minimal