diff --git a/.github/workflows/nix-integration-test.yml b/.github/workflows/nix-integration-test.yml
index ac35238..ed10607 100644
--- a/.github/workflows/nix-integration-test.yml
+++ b/.github/workflows/nix-integration-test.yml
@@ -13,5 +13,5 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493 # v4.1.1
-      - uses: DeterminateSystems/nix-installer-action@786fff0690178f1234e4e1fe9b536e94f5433196 # v20
+      - uses: DeterminateSystems/nix-installer-action@c5a866b6ab867e88becbed4467b93592bce69f8a # v21
       - run: nix flake check
diff --git a/.github/workflows/update-flake-lock.yml b/.github/workflows/update-flake-lock.yml
index 7e46e1a..12cd142 100644
--- a/.github/workflows/update-flake-lock.yml
+++ b/.github/workflows/update-flake-lock.yml
@@ -14,6 +14,6 @@ jobs:
       - uses: actions/checkout@ff7abcd0c3c05ccf6adc123a8cd1fd4fb30fb493 # v4.1.1
         with:
           ssh-key: ${{ secrets.UPDATE_FLAKE_LOCK_SSH_KEY }}
-      - uses: DeterminateSystems/nix-installer-action@786fff0690178f1234e4e1fe9b536e94f5433196 # v20
+      - uses: DeterminateSystems/nix-installer-action@c5a866b6ab867e88becbed4467b93592bce69f8a # v21
       - name: Update flake.lock
         uses: DeterminateSystems/update-flake-lock@c5930b397a673a70ca70be06020e943aeac310a1 # v27