diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index 4c2b8d7..1e1df27 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -17,7 +17,7 @@ jobs:
       with:
           # Nix Flakes doesn't work on shallow clones
           fetch-depth: 0
-    - uses: cachix/install-nix-action@v20
+    - uses: cachix/install-nix-action@v21
       with:
         github_access_token: ${{ secrets.GITHUB_TOKEN }}
         extra_nix_config: |
diff --git a/.github/workflows/update-flake-lock.yml b/.github/workflows/update-flake-lock.yml
index d0ec576..785d291 100644
--- a/.github/workflows/update-flake-lock.yml
+++ b/.github/workflows/update-flake-lock.yml
@@ -11,7 +11,7 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v3
       - name: Install Nix
-        uses: cachix/install-nix-action@v20
+        uses: cachix/install-nix-action@v21
         with:
           extra_nix_config: |
             access-tokens = github.com=${{ secrets.GITHUB_TOKEN }}