diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 00000000..d89d38d5
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,16 @@
+version: 2
+
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+    cooldown:
+      default-days: 7
+    groups:
+      actions:
+        patterns: ["*"]
+    ignore:
+      - dependency-name: DeterminateSystems/*
+    commit-message:
+      prefix: ci
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7c60d3a4..f1801db2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -16,7 +16,9 @@ jobs:
       contents: read
     steps:
       - name: git checkout
-        uses: actions/checkout@v6
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
 
       - name: Check Nixpkgs input
         uses: DeterminateSystems/flake-checker-action@main
@@ -31,7 +33,7 @@ jobs:
           echo "NPM_CACHE_DIRECTORY=$(nix develop --command npm config get cache | tr -d '\n')" >> $GITHUB_ENV
 
       - name: Set up npm cache
-        uses: actions/cache@v5
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: ${{ env.NPM_CACHE_DIRECTORY }}
           key: npm-cache-${{ hashFiles('**/package-lock.json') }}
@@ -39,7 +41,7 @@ jobs:
             npm-cache
 
       - name: Restore Lychee cache
-        uses: actions/cache@v5
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: .lycheecache
           key: lychee-cache-${{ github.sha }}
@@ -49,7 +51,7 @@ jobs:
         run: nix develop --command ci
 
       - name: Check external links
-        uses: lycheeverse/lychee-action@v2
+        uses: lycheeverse/lychee-action@8646ba30535128ac92d33dfc9133794bfdd9b411 # v2.8.0
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
@@ -62,7 +64,7 @@ jobs:
 
       - name: Save Lychee cache
         if: success() || failure()
-        uses: actions/cache/save@v5
+        uses: actions/cache/save@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: .lycheecache
           key: cache-lychee-${{ github.sha }}
@@ -87,7 +89,9 @@ jobs:
           - nix-system: x86_64-linux
             runner: UbuntuLatest32Cores128G
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
       - uses: DeterminateSystems/determinate-nix-action@main
       - uses: DeterminateSystems/flakehub-cache-action@main
 
diff --git a/.github/workflows/flakehub-cache.yml b/.github/workflows/flakehub-cache.yml
index 317aea32..b763c75c 100644
--- a/.github/workflows/flakehub-cache.yml
+++ b/.github/workflows/flakehub-cache.yml
@@ -20,7 +20,9 @@ jobs:
           - nix-system: x86_64-linux
             runner: UbuntuLatest32Cores128G
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
       - uses: DeterminateSystems/determinate-nix-action@main
       - uses: DeterminateSystems/flakehub-cache-action@main
       - name: Build dev shell for ${{ matrix.systems.nix-system }} on ${{ matrix.systems.runner }}
diff --git a/.github/workflows/flakehub-publish-rolling.yml b/.github/workflows/flakehub-publish-rolling.yml
index d3711990..d1d03a0c 100644
--- a/.github/workflows/flakehub-publish-rolling.yml
+++ b/.github/workflows/flakehub-publish-rolling.yml
@@ -12,7 +12,9 @@ jobs:
       id-token: write
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
       - uses: DeterminateSystems/determinate-nix-action@main
       - uses: DeterminateSystems/flakehub-push@main
         with:
diff --git a/.github/workflows/update-flake-lock.yml b/.github/workflows/update-flake-lock.yml
index 0acb9c2c..1faff89a 100644
--- a/.github/workflows/update-flake-lock.yml
+++ b/.github/workflows/update-flake-lock.yml
@@ -14,8 +14,10 @@ jobs:
       pull-requests: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
-      - uses: DeterminateSystems/determinate-nix-action@v3
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
+      - uses: DeterminateSystems/determinate-nix-action@9adf02b41cfdac2632e1c16f0480ff5bf3b05dd6 # v3.21.1
       - uses: DeterminateSystems/update-flake-lock@main
         with:
           pr-title: "Update root Nix flake inputs" # Title of PR to be created
@@ -31,8 +33,10 @@ jobs:
       pull-requests: write
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
-      - uses: DeterminateSystems/determinate-nix-action@v3
+      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
+      - uses: DeterminateSystems/determinate-nix-action@9adf02b41cfdac2632e1c16f0480ff5bf3b05dd6 # v3.21.1
       - uses: DeterminateSystems/flakehub-cache-action@main
       - name: Update template flake.lock files
         id: update
@@ -48,7 +52,7 @@ jobs:
           fi
       - name: Create pull request for changes
         if: ${{ steps.detect-changes.outputs.changed == 'true' }}
-        uses: peter-evans/create-pull-request@v7
+        uses: peter-evans/create-pull-request@5f6978faf089d4d20b00c7766989d076bb2fc7f1 # v8.1.1
         with:
           base: main
           branch: flake-template-input-update
diff --git a/.github/workflows/zizmor.yml b/.github/workflows/zizmor.yml
new file mode 100644
index 00000000..9397c97f
--- /dev/null
+++ b/.github/workflows/zizmor.yml
@@ -0,0 +1,25 @@
+name: zizmor
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  zizmor:
+    runs-on: ubuntu-latest
+    permissions:
+      security-events: write
+      contents: read
+      actions: read
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        with:
+          persist-credentials: false
+
+      - name: Run zizmor
+        uses: zizmorcore/zizmor-action@5f14fd08f7cf1cb1609c1e344975f152c7ee938d # v0.5.6
+        with:
+          config: .github/zizmor.yml
diff --git a/.github/zizmor.yml b/.github/zizmor.yml
new file mode 100644
index 00000000..abdc40be
--- /dev/null
+++ b/.github/zizmor.yml
@@ -0,0 +1,5 @@
+rules:
+  unpinned-uses:
+    config:
+      policies:
+        DeterminateSystems/*: ref-pin