diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index 07b514d5..c1eef07f 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -15,7 +15,7 @@ jobs:
     steps:
     - name: install ninja
       run: sudo apt install ninja-build
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: clone-vcpkg
       working-directory: "${{runner.temp}}"
       run: >
@@ -63,7 +63,7 @@ jobs:
     steps:
       - name: install ninja
         run: sudo apt install ninja-build
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: cache-vcpkg
         id: cache-vcpkg
         uses: actions/cache@v4
@@ -132,7 +132,7 @@ jobs:
           restore-keys: |
             vcpkg-${{ env.vcpkg_SHA }}-build-msvc-2019-2-
 
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: ilammy/msvc-dev-cmd@v1
       - name: configure
         run: |
@@ -159,7 +159,7 @@ jobs:
     steps:
       - name: install ninja
         run: brew install ninja
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: clone-vcpkg
         working-directory: "${{runner.temp}}"
         run: >
diff --git a/.github/workflows/coverage.yaml b/.github/workflows/coverage.yaml
index bd5cab46..fbea9366 100644
--- a/.github/workflows/coverage.yaml
+++ b/.github/workflows/coverage.yaml
@@ -15,7 +15,7 @@ jobs:
     steps:
     - name: install tools
       run: sudo apt install ninja-build lcov
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - name: clone-vcpkg
       working-directory: "${{runner.temp}}"
       run: >
diff --git a/.github/workflows/install.yaml b/.github/workflows/install.yaml
index 604b6fc3..793dc1ad 100644
--- a/.github/workflows/install.yaml
+++ b/.github/workflows/install.yaml
@@ -12,7 +12,7 @@ jobs:
     steps:
       - name: install-dependencies
         run: sudo apt install ninja-build libboost-dev libboost-program-options-dev nlohmann-json3-dev libabsl-dev
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: configure
         run: >
           cmake -S . -B ${{runner.temp}}/build -GNinja -DBUILD_TESTING=OFF
@@ -37,7 +37,7 @@ jobs:
       - name: install-dependencies
         run: >
           sudo apt install ninja-build libboost-dev libboost-program-options-dev nlohmann-json3-dev libabsl-dev
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: configure
         run: >
           cmake -S . -B ${{runner.temp}}/build -GNinja
diff --git a/.github/workflows/style.yaml b/.github/workflows/style.yaml
index dc2ab80e..134c1773 100644
--- a/.github/workflows/style.yaml
+++ b/.github/workflows/style.yaml
@@ -13,7 +13,7 @@ jobs:
     name: clang-format
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: clang-format
         run: >
           git ls-files -z -- '*.h' '*.cc' |
@@ -25,7 +25,7 @@ jobs:
     name: cmake-format
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: install cmake-format
         run: pip install cmakelang==0.6.13
       - name: cmake-format
@@ -39,7 +39,7 @@ jobs:
     name: generated-files
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - name: install ninja
         run: sudo apt install moreutils
       - name: regenerate-build-examples