diff --git a/plugins/custom_calyptia/calyptia.h b/plugins/custom_calyptia/calyptia.h
index ed54552a4cf..6f8e14c63df 100644
--- a/plugins/custom_calyptia/calyptia.h
+++ b/plugins/custom_calyptia/calyptia.h
@@ -20,6 +20,7 @@
 #ifndef FLB_CALYPTIA_H
 #define FLB_CALYPTIA_H
 
+#include <fluent-bit/flb_utils.h>
 #include <stdbool.h>
 
 struct calyptia {