diff --git a/lean-toolchain b/lean-toolchain
index 346aadd88f..bf10bf9c81 100644
--- a/lean-toolchain
+++ b/lean-toolchain
@@ -1 +1 @@
-leanprover/lean4:nightly-2021-10-16
+leanprover/lean4:nightly-2021-10-23