diff --git a/README.md b/README.md
index 05c2959..818e32e 100644
--- a/README.md
+++ b/README.md
@@ -18,3 +18,8 @@ cargo install mdbook
 mdbook serve docs
 ```
 
+## code
+`code`目录下的`rust-toolchain`内容为`nightly`。原则上，我们会采用`rustc`最新的版本。目前的版本信息如下：
+```
+rustc 1.55.0-nightly (952fdf2a1 2021-07-05)
+```
diff --git a/code/rust-toolchain b/code/rust-toolchain
index c3912e1..bf867e0 100644
--- a/code/rust-toolchain
+++ b/code/rust-toolchain
@@ -1 +1 @@
-nightly-2021-03-01
\ No newline at end of file
+nightly