diff --git a/.github/workflows/flake-test.yml b/.github/workflows/flake-test.yml
index 35fec97..61d8221 100644
--- a/.github/workflows/flake-test.yml
+++ b/.github/workflows/flake-test.yml
@@ -13,7 +13,7 @@ jobs:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
-      - uses: DeterminateSystems/nix-installer-action@v20
+      - uses: DeterminateSystems/nix-installer-action@v21
       - uses: cachix/cachix-action@v16
         with:
           name: zz-flutter-client
@@ -31,7 +31,7 @@ jobs:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
-      - uses: DeterminateSystems/nix-installer-action@v20
+      - uses: DeterminateSystems/nix-installer-action@v21
       - uses: cachix/cachix-action@v16
         with:
           name: zz-flutter-client