diff --git a/.github/workflows/flake_update.yaml b/.github/workflows/flake_update.yaml
new file mode 100644
index 0000000..a4ba67a
--- /dev/null
+++ b/.github/workflows/flake_update.yaml
@@ -0,0 +1,32 @@
+name: "flake_update"
+
+on:
+  workflow_dispatch:
+  schedule:
+    # At 7:00am on Monday
+    - cron: "0 7 * * 1"
+
+jobs:
+  flake_update:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install nix
+        uses: cachix/install-nix-action@v25
+        with:
+          install_url: https://releases.nixos.org/nix/nix-2.20.4/install
+
+      - name: Flake update
+        run: |
+          nix flake update
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v6
+        with:
+          commit-message: "chore(nix): update flake.lock"
+          title: "Update flake.lock"
+          body: "This PR updates the flake.lock file."
+          branch: "update-flake-lock"
+          branch-suffix: "short-commit-hash"
+          base: "main"
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index ea22445..2773975 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -34,6 +34,8 @@ jobs:
 
       - name: Install nix
         uses: cachix/install-nix-action@v25
+        with:
+          install_url: https://releases.nixos.org/nix/nix-2.20.4/install
 
       - name: Set up cachix
         uses: cachix/cachix-action@v14