diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 759172b..edb2958 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         os:
-          - macos-latest
+          - macos-13
           - ubuntu-latest
           - windows-latest
         ocaml-compiler: