diff --git a/systemd_service_parser.cpp b/systemd_service_parser.cpp
index 46d9156..3258b36 100644
--- a/systemd_service_parser.cpp
+++ b/systemd_service_parser.cpp
@@ -15,7 +15,7 @@
         std::ifstream fileStream(jsonFile);
         auto j = json::parse(fileStream);
 
-        for (auto& service : j["services"].items())
+        for (const auto& service : j["services"].items())
         {
             if (gVerbose)
             {