diff --git a/.github/workflows/acl2.yml b/.github/workflows/acl2.yml
index 3c2bad771b..7c9d0820fd 100644
--- a/.github/workflows/acl2.yml
+++ b/.github/workflows/acl2.yml
@@ -16,7 +16,7 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: nightly
+          toolchain: stable
           override: true
 
       - name: Prepare tgc