diff --git a/internal/sys/syscall_windows_arm64.go b/internal/sys/syscall_windows_arm64.go
new file mode 100644
index 0000000..7841818
--- /dev/null
+++ b/internal/sys/syscall_windows_arm64.go
@@ -0,0 +1,14 @@
+//
+// go.notify/internal/sys :: syscall_windows_arm64.go
+//
+//   Copyright (c) 2017-2019 Akinori Hattori <hattya@gmail.com>
+//
+//   SPDX-License-Identifier: MIT
+//
+
+package sys
+
+var (
+	GetWindowLongPtr = getWindowLongPtr
+	SetWindowLongPtr = setWindowLongPtr
+)