diff --git a/.github/workflows/check_amalgamation.yml b/.github/workflows/check_amalgamation.yml
index 0fadb5206..2475874a5 100644
--- a/.github/workflows/check_amalgamation.yml
+++ b/.github/workflows/check_amalgamation.yml
@@ -14,7 +14,7 @@ jobs:
           mkdir -p ./pr
           echo ${{ github.event.number }} > ./pr/number
           echo ${{ github.event.pull_request.user.login }} > ./pr/author
-      - uses: actions/upload-artifact@v2
+      - uses: actions/upload-artifact@v4
         with:
           name: pr
           path: pr/
@@ -33,13 +33,13 @@ jobs:
 
     steps:
       - name: Checkout pull request
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: main
           ref: ${{ github.event.pull_request.head.sha }}
 
       - name: Checkout tools
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: tools
           ref: develop
diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index 93923a182..7cbf7b39a 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -27,11 +27,11 @@ jobs:
 
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
 
     # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@v3
       with:
         languages: c-cpp
 
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index 9ac1fe3fa..b6b03f787 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -26,7 +26,7 @@ jobs:
       DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -D CMAKE_BUILD_TYPE=Debug -DJSON_BuildTests=On -DJSON_FastTests=ON
       - name: Build
@@ -43,7 +43,7 @@ jobs:
       DEVELOPER_DIR: /Applications/Xcode_${{ matrix.xcode }}.app/Contents/Developer
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -D CMAKE_BUILD_TYPE=Debug -DJSON_BuildTests=On -DJSON_FastTests=ON
       - name: Build
@@ -58,7 +58,7 @@ jobs:
         standard: [11, 14, 17, 20, 23]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -D CMAKE_BUILD_TYPE=Debug -DJSON_BuildTests=On -DJSON_TestStandards=${{ matrix.standard }}
       - name: Build
diff --git a/.github/workflows/publish_documentation.yml b/.github/workflows/publish_documentation.yml
index 5a32d13a4..1d1973d77 100644
--- a/.github/workflows/publish_documentation.yml
+++ b/.github/workflows/publish_documentation.yml
@@ -23,7 +23,7 @@ jobs:
     if: github.repository == 'nlohmann/json'
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install and update PlantUML
         run: sudo apt-get update ; sudo apt-get install -y plantuml
@@ -35,7 +35,7 @@ jobs:
         run: make build -C docs/mkdocs
 
       - name: Deploy documentation
-        uses: peaceiris/actions-gh-pages@v3
+        uses: peaceiris/actions-gh-pages@v4
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
           publish_dir: ./docs/mkdocs/site
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 35fb9573c..c04904db1 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -23,7 +23,7 @@ jobs:
     steps:
       - name: Install git and unzip
         run: apt-get update ; apt-get install -y git unzip
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -35,7 +35,7 @@ jobs:
     runs-on: ubuntu-latest
     container: ghcr.io/nlohmann/json-ci:v2.4.0
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -48,7 +48,7 @@ jobs:
       matrix:
         target: [ci_cppcheck, ci_test_valgrind, ci_test_amalgamation, ci_test_single_header, ci_single_binaries, ci_infer]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -60,7 +60,7 @@ jobs:
       matrix:
         target: [ci_cpplint, ci_reproducible_tests, ci_non_git_tests, ci_offline_testdata]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -77,7 +77,7 @@ jobs:
     steps:
       - name: Install git, clang-tools, and unzip
         run: apt-get update ; apt-get install -y git clang-tools unzip
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -94,7 +94,7 @@ jobs:
     steps:
       - name: Install build-essential
         run: apt-get update ; apt-get install -y build-essential unzip wget git
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -109,7 +109,7 @@ jobs:
       contents: read
       checks: write
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -132,7 +132,7 @@ jobs:
         compiler: ['4', '5', '6', '7', '8', '9', '10', '11', '12', 'latest']
     container: gcc:${{ matrix.compiler }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -149,7 +149,7 @@ jobs:
     steps:
       - name: Install unzip and git
         run: apt-get update ; apt-get install -y unzip git
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Set env FORCE_STDCPPFS_FLAG for clang 7 / 8 / 9 / 10
@@ -167,7 +167,7 @@ jobs:
       matrix:
         compiler: [g++-4.8]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -180,7 +180,7 @@ jobs:
       matrix:
         standard: [11, 14, 17, 20, 23]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -195,7 +195,7 @@ jobs:
     steps:
       - name: Install git and unzip
         run: apt-get update ; apt-get install -y git unzip
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Get latest CMake and ninja
         uses: lukka/get-cmake@v3.27.7
       - name: Run CMake
@@ -207,7 +207,7 @@ jobs:
     runs-on: ubuntu-latest
     container: ghcr.io/nlohmann/json-ci:v2.4.0
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
@@ -228,7 +228,7 @@ jobs:
   ci_reuse_compliance:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-python@v3
       - name: Install REUSE tool
         run:  python -m pip install reuse
@@ -241,7 +241,7 @@ jobs:
       matrix:
         target: [ci_test_examples, ci_test_api_documentation]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -DJSON_CI=On
       - name: Build
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 7ddd4be25..292dea0d2 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -24,7 +24,7 @@ jobs:
         architecture: [x64, x86]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Set up MinGW
         uses: egor-tensin/setup-mingw@v2
         with:
@@ -45,7 +45,7 @@ jobs:
         architecture: [Win32, x64]
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Run CMake
       run: cmake -S . -B build -G "Visual Studio 16 2019" -A ${{ matrix.architecture }} -DJSON_BuildTests=On -DCMAKE_CXX_FLAGS="/W4 /WX"
       if: matrix.build_type == 'Release'
@@ -61,7 +61,7 @@ jobs:
     runs-on: windows-2019
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Run CMake
       run: cmake -S . -B build -G "Visual Studio 16 2019" -DJSON_BuildTests=On -DCMAKE_CXX_FLAGS="/permissive- /std:c++latest /utf-8 /W4 /WX"
     - name: Build
@@ -77,7 +77,7 @@ jobs:
         architecture: [Win32, x64]
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Run CMake
       run: cmake -S . -B build -G "Visual Studio 17 2022" -A ${{ matrix.architecture }} -DJSON_BuildTests=On -DCMAKE_CXX_FLAGS="/W4 /WX"
       if: matrix.build_type == 'Release'
@@ -93,7 +93,7 @@ jobs:
     runs-on: windows-2022
 
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Run CMake
       run: cmake -S . -B build -G "Visual Studio 17 2022" -DJSON_BuildTests=On -DCMAKE_CXX_FLAGS="/permissive- /std:c++latest /utf-8 /W4 /WX"
     - name: Build
@@ -108,7 +108,7 @@ jobs:
         version: [11, 12, 13, 14, 15]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install Clang
         run: curl -fsSL -o LLVM${{ matrix.version }}.exe https://github.com/llvm/llvm-project/releases/download/llvmorg-${{ matrix.version }}.0.0/LLVM-${{ matrix.version }}.0.0-win64.exe ; 7z x LLVM${{ matrix.version }}.exe -y -o"C:/Program Files/LLVM"
       - name: Run CMake
@@ -125,7 +125,7 @@ jobs:
         architecture: [Win32, x64]
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Run CMake
         run: cmake -S . -B build -G "Visual Studio 16 2019" -A ${{ matrix.architecture }} -T ClangCL -DJSON_BuildTests=On
       - name: Build