diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index db86156..10f7e30 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -4,13 +4,17 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "daily"
-    # Too noisy. See https://github.community/t/increase-if-necessary-for-github-actions-in-dependabot/179581
-    open-pull-requests-limit: 0
+      interval: "weekly"
+    cooldown:
+      default-days: 7
+    ignore:
+      - dependency-name: "yiisoft/*"
 
   # Maintain dependencies for Composer
   - package-ecosystem: "composer"
     directory: "/"
     schedule:
       interval: "daily"
+    cooldown:
+      default-days: 7
     versioning-strategy: increase-if-necessary
diff --git a/.github/workflows/bc.yml b/.github/workflows/bc.yml
index 53f95bf..1fb84f8 100644
--- a/.github/workflows/bc.yml
+++ b/.github/workflows/bc.yml
@@ -3,13 +3,18 @@ on:
   push:
 
 name: backwards compatibility
+
+permissions:
+  contents: read
 jobs:
   roave_bc_check:
     name: Roave BC Check
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@master
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5
+        with:
+          persist-credentials: false
       - name: fetch tags
         run: git fetch --depth=1 origin +refs/tags/*:refs/tags/*
       - name: Roave BC Check
-        uses: docker://nyholm/roave-bc-check-ga
+        uses: docker://nyholm/roave-bc-check-ga@sha256:a9d3d932a4d3ba6a5a0563ef3788918a538198ee9c061a153f9b55caa8d3625f
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index da97b58..40a3f06 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -21,6 +21,9 @@ on:
 
 name: build
 
+permissions:
+  contents: read
+
 jobs:
   tests:
     name: PHP ${{ matrix.php }}-pgsql-${{ matrix.pgsql }}
@@ -61,10 +64,12 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5
+        with:
+          persist-credentials: false
 
       - name: Install PHP
-        uses: shivammathur/setup-php@v2
+        uses: shivammathur/setup-php@b604ade2a87db23f8871b7182e69ec5e75effb45
         with:
           php-version: ${{ matrix.php }}
           extensions: ${{ env.extensions }}
@@ -77,7 +82,7 @@ jobs:
         run: echo "COMPOSER_CACHE_DIR=$(composer config cache-dir)" >> $GITHUB_ENV
 
       - name: Cache dependencies installed with composer
-        uses: actions/cache@v2
+        uses: actions/cache@8492260343ad570701412c2f464a5877dc76bace
         with:
           path: ${{ env.COMPOSER_CACHE_DIR }}
           key: php${{ matrix.php }}-composer-${{ hashFiles('**/composer.json') }}
diff --git a/.github/workflows/mutation.yml b/.github/workflows/mutation.yml
index 08736d8..90942cb 100644
--- a/.github/workflows/mutation.yml
+++ b/.github/workflows/mutation.yml
@@ -19,6 +19,9 @@ on:
 
 name: mutation test
 
+permissions:
+  contents: read
+
 jobs:
   mutation:
     name: PHP ${{ matrix.php }}-${{ matrix.os }}
@@ -49,10 +52,12 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5
+        with:
+          persist-credentials: false
 
       - name: Install PHP
-        uses: shivammathur/setup-php@v2
+        uses: shivammathur/setup-php@b604ade2a87db23f8871b7182e69ec5e75effb45
         with:
           php-version: ${{ matrix.php }}
           extensions: ${{ env.extensions }}
@@ -64,7 +69,7 @@ jobs:
         run: echo "COMPOSER_CACHE_DIR=$(composer config cache-dir)" >> $GITHUB_ENV
 
       - name: Cache dependencies installed with composer
-        uses: actions/cache@v2
+        uses: actions/cache@8492260343ad570701412c2f464a5877dc76bace
         with:
           path: ${{ env.COMPOSER_CACHE_DIR }}
           key: php${{ matrix.php }}-composer-${{ hashFiles('**/composer.json') }}
diff --git a/.github/workflows/static.yml b/.github/workflows/static.yml
index 1a70e3d..3403e73 100644
--- a/.github/workflows/static.yml
+++ b/.github/workflows/static.yml
@@ -21,6 +21,9 @@ on:
 
 name: static analysis
 
+permissions:
+  contents: read
+
 jobs:
   mutation:
     name: PHP ${{ matrix.php }}-${{ matrix.os }}
@@ -42,10 +45,12 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5
+        with:
+          persist-credentials: false
 
       - name: Install PHP
-        uses: shivammathur/setup-php@v2
+        uses: shivammathur/setup-php@b604ade2a87db23f8871b7182e69ec5e75effb45
         with:
           php-version: ${{ matrix.php }}
           extensions: ${{ env.extensions }}
@@ -56,7 +61,7 @@ jobs:
         run: echo "COMPOSER_CACHE_DIR=$(composer config cache-dir)" >> $GITHUB_ENV
 
       - name: Cache dependencies installed with composer
-        uses: actions/cache@v2
+        uses: actions/cache@8492260343ad570701412c2f464a5877dc76bace
         with:
           path: ${{ env.COMPOSER_CACHE_DIR }}
           key: php${{ matrix.php }}-composer-${{ hashFiles('**/composer.json') }}
diff --git a/.github/workflows/zizmor.yml b/.github/workflows/zizmor.yml
new file mode 100644
index 0000000..430255d
--- /dev/null
+++ b/.github/workflows/zizmor.yml
@@ -0,0 +1,22 @@
+name: GitHub Actions Security Analysis with zizmor 🌈
+
+on:
+  push:
+    branches:
+      - master
+      - main
+    paths:
+      - '.github/**.yml'
+      - '.github/**.yaml'
+  pull_request:
+    paths:
+      - '.github/**.yml'
+      - '.github/**.yaml'
+
+permissions:
+  actions: read # Required by zizmor when reading workflow metadata through the API.
+  contents: read # Required to read workflow files.
+
+jobs:
+  zizmor:
+    uses: yiisoft/actions/.github/workflows/zizmor.yml@master