diff --git a/internal/pause/impl_test.go b/internal/pause/impl_test.go
new file mode 100644
index 0000000..0093b27
--- /dev/null
+++ b/internal/pause/impl_test.go
@@ -0,0 +1,26 @@
+// ©Hayabusa Cloud Co., Ltd. 2025. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package pause
+
+import "testing"
+
+func TestPause_Branches(t *testing.T) {
+	// Exercise both branches in Pause.
+	Pause(-1)
+	Pause(0)
+	Pause(1)
+	Pause(2)
+	Pause(64)
+}
+
+func TestPause_NoAllocs(t *testing.T) {
+	allocs := testing.AllocsPerRun(1000, func() {
+		Pause(1)
+		Pause(2)
+	})
+	if allocs != 0 {
+		t.Fatalf("Pause allocated: got %v allocs/op, want 0", allocs)
+	}
+}