diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index ff4f2e31c..e4f159622 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -12,12 +12,9 @@ concurrency:
 jobs:
   tests:
     runs-on: ubuntu-latest
-    strategy:
-      matrix:
-        ocamlVersion: [5_2]
     steps:
     - uses: actions/checkout@v4
-    - uses: cachix/install-nix-action@v27
+    - uses: cachix/install-nix-action@v31
       with:
         extra_nix_config: |
           extra-substituters = https://anmonteiro.nix-cache.workers.dev