diff --git a/pkg/mining/manager.go b/pkg/mining/manager.go
index d36dec2..8158511 100644
--- a/pkg/mining/manager.go
+++ b/pkg/mining/manager.go
@@ -218,12 +218,12 @@ func findAvailablePort() (int, error) {
 	if err != nil {
 		return 0, err
 	}
-	l, err := net.ListenTCP("tcp", addr)
+	listener, err := net.ListenTCP("tcp", addr)
 	if err != nil {
 		return 0, err
 	}
-	defer l.Close()
-	return l.Addr().(*net.TCPAddr).Port, nil
+	defer listener.Close()
+	return listener.Addr().(*net.TCPAddr).Port, nil
 }
 
 // StartMiner starts a new miner and saves its configuration.