diff --git a/internal/csync/slices_test.go b/internal/csync/slices_test.go
index d1c7af8cf30f3d58a84046f899f8dd89f80beb51..31f70d73c4b1c975592c17cf41cf0d57b0050b43 100644
--- a/internal/csync/slices_test.go
+++ b/internal/csync/slices_test.go
@@ -70,6 +70,7 @@ func TestLazySlice_EarlyBreak(t *testing.T) {
 
 	data := []string{"a", "b", "c", "d", "e"}
 	s := NewLazySlice(func() []string {
+		// TODO: use synctest when new Go is out.
 		time.Sleep(10 * time.Millisecond) // Small delay to ensure loading happens
 		return data
 	})