diff --git a/libs/cputimeinstate/cputimeinstate.h b/libs/cputimeinstate/cputimeinstate.h
index 0205452..9f6103e 100644
--- a/libs/cputimeinstate/cputimeinstate.h
+++ b/libs/cputimeinstate/cputimeinstate.h
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#pragma once
+
 #include <unordered_map>
 #include <vector>