diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..d89d38d
--- /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.yaml b/.github/workflows/ci.yaml
index ecd5dcb..9fce11e 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -13,8 +13,10 @@ jobs:
       contents: read
       id-token: write
     steps:
-      - uses: actions/checkout@v6
-      - uses: DeterminateSystems/determinate-nix-action@v3
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - uses: DeterminateSystems/determinate-nix-action@main
       - uses: DeterminateSystems/flakehub-cache-action@main
 
       - name: Get npm cache directory
@@ -23,7 +25,7 @@ jobs:
           echo "directory=$(nix develop --command npm config get cache | tr -d '\n')" >> $GITHUB_OUTPUT
 
       - name: Set up npm cache
-        uses: actions/cache@v4
+        uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
           path: ${{ steps.npm-cache-directory.outputs.directory }}
           key: flake-checker-action-npm-cache-${{ hashFiles('**/package-lock.json') }}
@@ -46,8 +48,12 @@ jobs:
     name: Run x86_64 Linux (clean)
     needs: build-check-typescript
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Check flake.lock
         uses: ./
         with:
@@ -57,8 +63,12 @@ jobs:
     name: Run x86_64 Linux (dirty)
     needs: build-check-typescript
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Check flake.lock
         uses: ./
         with:
@@ -69,8 +79,12 @@ jobs:
     name: Run x86_64 Darwin (clean)
     needs: build-check-typescript
     runs-on: macos-latest
+    permissions:
+      contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Check flake.lock
         uses: ./
         with:
@@ -80,8 +94,12 @@ jobs:
     name: Run x86_64 Darwin (dirty)
     needs: build-check-typescript
     runs-on: macos-latest
+    permissions:
+      contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
       - name: Check flake.lock
         uses: ./
         with:
@@ -90,6 +108,8 @@ jobs:
 
   success:
     name: Success
+    permissions:
+      contents: read
     needs:
       - run-x86_64-linux-clean
       - run-x86_64-linux-dirty
diff --git a/.github/workflows/zizmor.yml b/.github/workflows/zizmor.yml
new file mode 100644
index 0000000..e6a3c98
--- /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@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        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 0000000..abdc40b
--- /dev/null
+++ b/.github/zizmor.yml
@@ -0,0 +1,5 @@
+rules:
+  unpinned-uses:
+    config:
+      policies:
+        DeterminateSystems/*: ref-pin