diff --git a/NOTE.md b/NOTE.md
new file mode 100644
index 0000000..21f8032
--- /dev/null
+++ b/NOTE.md
@@ -0,0 +1,3 @@
+想要删除类型系统，
+但是发现很难在现有代码的基础上删除类型系统，
+还是重写一个比较好。
diff --git a/TODO.md b/TODO.md
index bcf5025..dce435c 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,7 +1,2 @@
-删除类型系统，并补充相关笔记
-更改命名惯例为 lisp-case
-
-# later
-
 static import should handled by an extra pass -- instead of injecting a `Loader` to `Mod`
 `NodeId` vs `Node` -- instead of `Node` vs `NodeEntry` -- the same for `HalfEdge`