diff --git a/.github/workflows/docgen.yml b/.github/workflows/docgen.yml
index cb297d1..6b9c513 100644
--- a/.github/workflows/docgen.yml
+++ b/.github/workflows/docgen.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: cachix/install-nix-action@v26
+      - uses: cachix/install-nix-action@V27
       - uses: cachix/cachix-action@v14
         with:
           name: mrcjkb
diff --git a/.github/workflows/nix-build.yml b/.github/workflows/nix-build.yml
index 604ba5b..e1bd61c 100644
--- a/.github/workflows/nix-build.yml
+++ b/.github/workflows/nix-build.yml
@@ -7,5 +7,5 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
-    - uses: cachix/install-nix-action@v26
+    - uses: cachix/install-nix-action@V27
     - run: nix flake check -L