diff --git a/metrics/darwin/interface.go b/metrics/darwin/interface.go
index d2678e8e0..e3debe875 100644
--- a/metrics/darwin/interface.go
+++ b/metrics/darwin/interface.go
@@ -14,6 +14,7 @@ import (
 
 	"github.com/mackerelio/mackerel-agent/logging"
 	"github.com/mackerelio/mackerel-agent/metrics"
+	"github.com/mackerelio/mackerel-agent/util"
 )
 
 /*