diff --git a/pid/builder.hpp b/pid/builder.hpp
index a493a67..0ee3420 100644
--- a/pid/builder.hpp
+++ b/pid/builder.hpp
@@ -8,7 +8,12 @@
 #include <memory>
 #include <unordered_map>
 
+namespace pid_control
+{
+
 std::unordered_map<int64_t, std::unique_ptr<PIDZone>>
     buildZones(const std::map<int64_t, conf::PIDConf>& zonePids,
                std::map<int64_t, struct conf::ZoneConfig>& zoneConfigs,
                SensorManager& mgr, sdbusplus::bus::bus& modeControlBus);
+
+}