diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index bfe0902..f46cfb0 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -4,4 +4,6 @@ updates:
     directory: /
     schedule:
       interval: monthly
+    cooldown:
+      default-days: 7
     open-pull-requests-limit: 2
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 6f3973a..07518ac 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -2,261 +2,53 @@ name: CI
 
 on: [push, pull_request]
 
+permissions: {}
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.ref }}
+  cancel-in-progress: true
+
 jobs:
   whitespace-errors:
+    name: Check for whitespace errors
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      with:
+        persist-credentials: false
     - name: check
       run: git diff-index --check --cached 4b825dc642cb6eb9a060e54bf8d69288fbee4904
 
-  gcc14-x86_64:
-    runs-on: ubuntu-24.04
-    env:
-      CC: gcc-14
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc13-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: gcc-13
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc12-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: gcc-12
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc11-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: gcc-11
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc10-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: gcc-10
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc9-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: gcc
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  gcc8-x86_64:
-    runs-on: ubuntu-20.04
-    env:
-      CC: gcc-8
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang18-x86_64:
-    runs-on: ubuntu-24.04
-    env:
-      CC: clang-18
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang17-x86_64:
-    runs-on: ubuntu-24.04
-    env:
-      CC: clang-17
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang16-x86_64:
-    runs-on: ubuntu-24.04
-    env:
-      CC: clang-16
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang15-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: clang-15
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang14-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: clang-14
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang13-x86_64:
-    runs-on: ubuntu-22.04
-    env:
-      CC: clang-13
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang12-x86_64:
-    runs-on: ubuntu-22.04
-    env:
-      CC: clang-12
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang11-x86_64:
-    runs-on: ubuntu-22.04
-    env:
-      CC: clang-11
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang10-x86_64:
-    runs-on: ubuntu-latest
-    env:
-      CC: clang
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang9-x86_64:
-    runs-on: ubuntu-20.04
-    env:
-      CC: clang-9
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
-    - name: install dependencies
-      run: ci/install-dependencies.sh
-    - name: build check
-      run: ci/run-build-and-tests.sh
-
-  clang8-x86_64:
-    runs-on: ubuntu-20.04
-    env:
-      CC: clang-8
-      TARGET: x86_64
-    steps:
-    - uses: actions/checkout@v6
-      with:
-        fetch-depth: 0
+  build-check:
+    runs-on: ${{ matrix.runs-on }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - { cc: gcc-14, runs-on: ubuntu-latest }
+          - { cc: gcc-13, runs-on: ubuntu-latest }
+          - { cc: gcc-12, runs-on: ubuntu-latest }
+          - { cc: gcc-11, runs-on: ubuntu-latest }
+          - { cc: gcc-10, runs-on: ubuntu-latest }
+          - { cc: gcc-9, runs-on: ubuntu-latest }
+          - { cc: clang-19, runs-on: ubuntu-latest }
+          - { cc: clang-18, runs-on: ubuntu-latest }
+          - { cc: clang-17, runs-on: ubuntu-latest }
+          - { cc: clang-16, runs-on: ubuntu-latest }
+          - { cc: clang-15, runs-on: ubuntu-latest }
+          - { cc: clang-14, runs-on: ubuntu-latest }
+          - { cc: clang-13, runs-on: ubuntu-22.04 }
+          - { cc: clang-12, runs-on: ubuntu-22.04 }
+          - { cc: clang-11, runs-on: ubuntu-22.04 }
+    name: Build ${{ matrix.cc }}-${{ matrix.runs-on }}
+    env:
+      CC: ${{ matrix.cc }}
+      TARGET: x86_64
+    steps:
+    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+      with:
+        fetch-depth: 0
+        persist-credentials: false
     - name: install dependencies
       run: ci/install-dependencies.sh
     - name: build check