diff --git a/metropolis/test/nanoswitch/nanoswitch.go b/metropolis/test/nanoswitch/nanoswitch.go
index 0bc65bd..b4ced56 100644
--- a/metropolis/test/nanoswitch/nanoswitch.go
+++ b/metropolis/test/nanoswitch/nanoswitch.go
@@ -187,7 +187,7 @@
 		Scope: netlink.SCOPE_UNIVERSE,
 	}
 	if err := netlink.RouteAdd(route); err != nil {
-		return fmt.Errorf("could not add default route: netlink.RouteAdd(%+v): %v", route, err)
+		return fmt.Errorf("could not add default route: netlink.RouteAdd(%+v): %w", route, err)
 	}
 	return nil
 }