diff --git a/.gitignore b/.gitignore
index 20c60d7..1824d0c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 /build
+/lakefile.olean
 /lake-packages/*
diff --git a/lean-toolchain b/lean-toolchain
index 49fd71c..a9bddf0 100644
--- a/lean-toolchain
+++ b/lean-toolchain
@@ -1 +1 @@
-leanprover/lean4:4.0.0
+leanprover/lean4:4.1.0