fix version comments for actions/checkout
diff --git a/.github/workflows/dev-long-tests.yml b/.github/workflows/dev-long-tests.yml
index e2081ee..762f07a 100644
--- a/.github/workflows/dev-long-tests.yml
+++ b/.github/workflows/dev-long-tests.yml
@@ -15,7 +15,7 @@
   make-all:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make all
       run: make all
 
@@ -26,7 +26,7 @@
       DEVNULLRIGHTS: 1
       READFROMBLOCKDEVICE: 1
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make test
       run: make test
 
@@ -34,7 +34,7 @@
   make-test-osx:
     runs-on: macos-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: OS-X test
       run: make test # make -c lib all doesn't work because of the fact that it's not a tty
 
@@ -45,7 +45,7 @@
       DEVNULLRIGHTS: 1
       READFROMBLOCKDEVICE: 1
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make test
       run: |
         sudo apt-get -qqq update
@@ -55,21 +55,21 @@
   no-intrinsics-fuzztest:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: no intrinsics fuzztest
       run: MOREFLAGS="-DZSTD_NO_INTRINSICS" make -C tests fuzztest
 
   tsan-zstreamtest:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: thread sanitizer zstreamtest
       run: CC=clang ZSTREAM_TESTTIME=-T3mn make tsan-test-zstream
 
   ubsan-zstreamtest:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: undefined behavior sanitizer zstreamtest
       run: CC=clang make uasan-test-zstream
 
@@ -77,7 +77,7 @@
   tsan-fuzztest:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: thread sanitizer fuzztest
       run: CC=clang make tsan-fuzztest
 
@@ -85,7 +85,7 @@
   big-tests-zstreamtest32:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: zstream tests in 32bit mode, with big tests
       run: |
         sudo apt-get -qqq update
@@ -96,7 +96,7 @@
   gcc-8-asan-ubsan-testzstd:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: gcc-8 + ASan + UBSan + Test Zstd
       # See https://askubuntu.com/a/1428822
       run: |
@@ -108,14 +108,14 @@
   clang-asan-ubsan-testzstd:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + ASan + UBSan + Test Zstd
       run: CC=clang make -j uasan-test-zstd </dev/null V=1
 
   gcc-asan-ubsan-testzstd-32bit:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: ASan + UBSan + Test Zstd, 32bit mode
       run: |
         sudo apt-get -qqq update
@@ -129,7 +129,7 @@
   gcc-8-asan-ubsan-fuzz:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: gcc-8 + ASan + UBSan + Fuzz Test
       # See https://askubuntu.com/a/1428822
       run: |
@@ -141,14 +141,14 @@
   clang-asan-ubsan-fuzz:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + ASan + UBSan + Fuzz Test
       run: CC=clang FUZZER_FLAGS="--long-tests" make clean uasan-fuzztest
 
   gcc-asan-ubsan-fuzz32:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: ASan + UBSan + Fuzz Test 32bit
       run: |
         sudo apt-get -qqq update
@@ -158,7 +158,7 @@
   clang-asan-ubsan-fuzz32:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + ASan + UBSan + Fuzz Test 32bit
       run: |
         sudo apt-get -qqq update
@@ -168,28 +168,28 @@
   asan-ubsan-regression:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: ASan + UBSan + Regression Test
       run: make -j uasanregressiontest
 
   clang-ubsan-regression:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + ASan + UBSan + Regression Test
       run: CC=clang make -j uasanregressiontest
 
   msan-regression:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: MSan + Regression Test
       run: make -j msanregressiontest
 
   clang-msan-fuzz-unoptimized:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: clang + MSan + Fuzz Test
         run: |
           sudo apt-get -qqq update
@@ -199,7 +199,7 @@
   clang-msan-fuzz:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + MSan + Fuzz Test
       run: |
         sudo apt-get -qqq update
@@ -210,7 +210,7 @@
   clang-msan-testzstd:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: clang + MSan + Test Zstd
       run: |
         sudo apt-get update
@@ -220,7 +220,7 @@
   armfuzz:
       runs-on: ubuntu-latest
       steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: Qemu ARM emulation + Fuzz Test
         run: |
           sudo apt-get -qqq update
@@ -230,7 +230,7 @@
   valgrind-fuzz-test:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: valgrind + fuzz test stack mode    # ~ 7mn
       shell: 'script -q -e -c "bash {0}"'
       run: |
@@ -246,7 +246,7 @@
       run:
         shell: msys2 {0}
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - uses: msys2/setup-msys2@5beef6d11f48bba68b9eb503e3adc60b23c0cc36 # tag=v2
       with:
         msystem: MINGW64
diff --git a/.github/workflows/dev-short-tests.yml b/.github/workflows/dev-short-tests.yml
index 9e337dc..3b2eb41 100644
--- a/.github/workflows/dev-short-tests.yml
+++ b/.github/workflows/dev-short-tests.yml
@@ -16,21 +16,21 @@
   linux-kernel:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: linux kernel, library + build + test
       run: make -C contrib/linux-kernel test CFLAGS="-Werror -Wunused-const-variable -Wunused-but-set-variable"
 
   benchmarking:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make benchmarking
       run: make benchmarking
 
   check-32bit: # designed to catch https://github.com/facebook/zstd/issues/2428
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make check on 32-bit
       run: |
         sudo apt update
@@ -40,7 +40,7 @@
   check-x32:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make check on x32 ABI # https://en.wikipedia.org/wiki/X32_ABI
       env:
         CHECK_CONSTRAINED_MEM: true
@@ -52,7 +52,7 @@
   build-c89:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: ensure zstd can be build with c89/c90 compilers (+ long long support + variadic macros)
       run: |
         make c89build V=1
@@ -60,16 +60,16 @@
   build-zstd-dll:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: build zstd bin against a dynamic lib (debuglevel for more dependencies)
       run: |
-        make -C lib lib-mt-release 
+        make -C lib lib-mt-release
         DEBUGLEVEL=2 make -C programs zstd-dll
 
   gcc-7-libzstd:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: gcc-7 + libzstdmt compilation
       # See https://askubuntu.com/a/1428822
       run: |
@@ -86,7 +86,7 @@
   cmake-build-and-test-check:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: cmake build and test check
       run: |
         FUZZERTEST=-T1mn ZSTREAM_TESTTIME=-T1mn make cmakebuild
@@ -97,7 +97,7 @@
   cpp-gnu90-c99-compatibility:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: C++, gnu90 and c99 compatibility
       run: |
         make cxxtest
@@ -111,7 +111,7 @@
   mingw-cross-compilation:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: mingw cross-compilation
       run: |
         # sudo update-alternatives --set x86_64-w64-mingw32-g++ /usr/bin/x86_64-w64-mingw32-g++-posix; (doesn't work)
@@ -122,7 +122,7 @@
   armbuild:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: ARM Build Test
       run: |
         sudo apt-get -qqq update
@@ -132,7 +132,7 @@
   bourne-shell:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Bourne shell compatibility (shellcheck)
       run: |
         wget https://github.com/koalaman/shellcheck/releases/download/v0.7.1/shellcheck-v0.7.1.linux.x86_64.tar.xz
@@ -142,7 +142,7 @@
   zlib-wrapper:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: zlib wrapper test
       run: |
         sudo apt-get -qqq update
@@ -153,7 +153,7 @@
   lz4-threadpool-libs:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: LZ4, thread pool, and libs build testslib wrapper test
       run: |
         make lz4install
@@ -167,7 +167,7 @@
   gcc-make-tests-32bit:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Make all, 32bit mode
       run: |
         sudo apt-get -qqq update
@@ -177,7 +177,7 @@
   gcc-8-make:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: gcc-8 build
         # See https://askubuntu.com/a/1428822
         run: |
@@ -200,7 +200,7 @@
             flags: "HAVE_ZLIB=0 HAVE_LZ4=0 HAVE_LZMA=1"
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: Build with ${{matrix.name}}
         run: ${{matrix.flags}} make zstd
 
@@ -208,7 +208,7 @@
   implicit-fall-through:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: -Wimplicit-fallthrough build
         run: |
           make clean
@@ -219,7 +219,7 @@
   meson-linux:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: Install packages
         run: |
           sudo apt-get update
@@ -243,7 +243,7 @@
   meson-windows:
     runs-on: windows-latest
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: Install packages
         run: pip install --pre meson
       - name: Initialize the MSVC dev command prompt
@@ -274,7 +274,7 @@
             flags: "-T ClangCL"
     runs-on: windows-2022
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Add MSBuild to PATH
       uses: microsoft/setup-msbuild@1ff57057b5cfdc39105cd07a01d78e9b0ea0c14c # tag=v1.3
     - name: Build
@@ -301,7 +301,7 @@
         ]
     runs-on: ${{matrix.runner}}
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Add MSBuild to PATH
       uses: microsoft/setup-msbuild@1ff57057b5cfdc39105cd07a01d78e9b0ea0c14c # tag=v1.3
     - name: Build ${{matrix.name}}
@@ -326,7 +326,7 @@
   libzstd-size:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: libzstd size test
       run: |
         make clean && make -j -C lib libzstd && ./tests/check_size.py lib/libzstd.so 1100000
@@ -337,7 +337,7 @@
   minimal-decompressor-macros:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: minimal decompressor macros
       run: |
         make clean && make -j all ZSTD_LIB_MINIFY=1 MOREFLAGS="-Werror"
@@ -354,7 +354,7 @@
   dynamic-bmi2:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: dynamic bmi2 tests
       run: |
         make clean && make -j check MOREFLAGS="-O0 -Werror -mbmi2"
@@ -366,7 +366,7 @@
   test-variants:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make all variants & validate
       run: |
         make -j -C programs allVariants MOREFLAGS=-O0
@@ -391,7 +391,7 @@
       XCC: ${{ matrix.xcc }}
       XEMU: ${{ matrix.xemu }}
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: apt update & install
       run: |
         sudo apt-get update
@@ -447,7 +447,7 @@
       run:
         shell: msys2 {0}
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - uses: msys2/setup-msys2@5beef6d11f48bba68b9eb503e3adc60b23c0cc36 # tag=v2
       with:
         msystem: ${{ matrix.msystem }}
@@ -483,7 +483,7 @@
         platform: [x64, Win32]
         configuration: [Release]
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Add MSBuild to PATH
       uses: microsoft/setup-msbuild@1ff57057b5cfdc39105cd07a01d78e9b0ea0c14c # tag=v1.3
     - name: Build and run tests
@@ -504,7 +504,7 @@
     runs-on: windows-latest
     steps:
     - run: git config --global core.autocrlf input
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - uses: cygwin/cygwin-install-action@006ad0b0946ca6d0a3ea2d4437677fa767392401 # tag=master
       with:
         platform: x86_64
@@ -529,7 +529,7 @@
   intel-cet-compatibility:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Build Zstd
       run: |
         make -j zstd V=1
@@ -550,7 +550,7 @@
     container:
       image: debian:testing
     steps:
-      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+      - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
       - name: Install dependencies
         run: |
           apt -y update
@@ -565,7 +565,7 @@
   versions-compatibility:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Versions Compatibility Test
       run: |
         make -C tests versionsTest
@@ -573,7 +573,7 @@
   clangbuild:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: make clangbuild
       run: |
         make clangbuild
@@ -581,7 +581,7 @@
   clang-pgo:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Build PGO Zstd with Clang
       env:
         CC: clang-14
@@ -593,7 +593,7 @@
   gcc-pgo:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - name: Build PGO Zstd with GCC
       env:
         CC: gcc
@@ -620,7 +620,7 @@
 #        sudo add-apt-repository "deb https://apt.repos.intel.com/oneapi all main"
 #        sudo apt-get update
 #        sudo apt-get install -y intel-basekit intel-hpckit
-#    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+#    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
 #    - name: make check
 #      run: |
 #        make CC=/opt/intel/oneapi/compiler/latest/linux/bin/intel64/icc check
diff --git a/.github/workflows/publish-release-artifacts.yml b/.github/workflows/publish-release-artifacts.yml
index c40fb6f..b2b4d50 100644
--- a/.github/workflows/publish-release-artifacts.yml
+++ b/.github/workflows/publish-release-artifacts.yml
@@ -17,7 +17,7 @@
 
     steps:
       - name: Checkout
-        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
 
       - name: Archive
         env:
diff --git a/.github/workflows/scorecards.yml b/.github/workflows/scorecards.yml
index 0673f7e..fa979b8 100644
--- a/.github/workflows/scorecards.yml
+++ b/.github/workflows/scorecards.yml
@@ -27,7 +27,7 @@
 
     steps:
       - name: "Checkout code"
-        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+        uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
         with:
           persist-credentials: false
 
diff --git a/.github/workflows/windows-artifacts.yml b/.github/workflows/windows-artifacts.yml
index 28e5997..5aac112 100644
--- a/.github/workflows/windows-artifacts.yml
+++ b/.github/workflows/windows-artifacts.yml
@@ -23,7 +23,7 @@
       run:
         shell: msys2 {0}
     steps:
-    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # tag=v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
     - uses: msys2/setup-msys2@5beef6d11f48bba68b9eb503e3adc60b23c0cc36 # tag=v2
       with:
         msystem: ${{ matrix.msystem }}