diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index a5e7972..0695acc 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -10,7 +10,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v3
-      - uses: cachix/install-nix-action@v18
+      - uses: cachix/install-nix-action@v20
         with:
           install_url: https://nixos.org/nix/install
           extra_nix_config: |
diff --git a/.github/workflows/fmt.yml b/.github/workflows/fmt.yml
index d785f5b..3350047 100644
--- a/.github/workflows/fmt.yml
+++ b/.github/workflows/fmt.yml
@@ -10,7 +10,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v3
-      - uses: cachix/install-nix-action@v18
+      - uses: cachix/install-nix-action@v20
         with:
           install_url: https://nixos.org/nix/install
           extra_nix_config: |