diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a3a0f28..f9f917c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,7 +20,7 @@ jobs:
     runs-on: "${{ matrix.os }}"
     steps:
       - uses: actions/checkout@v3
-      - uses: cachix/install-nix-action@v16
+      - uses: cachix/install-nix-action@v21
       - uses: cachix/cachix-action@v10
         with:
           name: tree-grepper
@@ -33,7 +33,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - uses: cachix/install-nix-action@v16
+      - uses: cachix/install-nix-action@v21
       - uses: cachix/cachix-action@v10
         with:
           name: tree-grepper