diff --git a/.github/workflows/autofix.yml b/.github/workflows/autofix.yml
index 65b212d5..16650f94 100644
--- a/.github/workflows/autofix.yml
+++ b/.github/workflows/autofix.yml
@@ -10,7 +10,7 @@ jobs:
     timeout-minutes: 1
     steps:
       # git-auto-commit-action is a bit tricky to use, see its README
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           repository: ${{ github.event.pull_request.head.repo.full_name }}
           ref: ${{ github.head_ref }}
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index 73cc95ff..4cebf1a9 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -9,14 +9,14 @@ jobs:
     timeout-minutes: 1
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: shellcheck --color=always --shell=bash --exclude=SC2086,SC2059,SC2046,SC2235,SC2002,SC2206,SC2068,SC2207,SC2013 *.sh activate
 
   editorconfig-checker:
     timeout-minutes: 1
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       # Hard-coded commit, because the latest changes aren't tagged.
       - uses: editorconfig-checker/action-editorconfig-checker@d4fca16fc71adef10fbe101903b654449fa9570c
         with:
@@ -27,7 +27,7 @@ jobs:
     timeout-minutes: 1
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
             python-version: '3.13'
diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 9ffe465e..6d339202 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -14,7 +14,7 @@ jobs:
         # Testing all levels because there was a bug that only happened with -O1. (#224)
         opt-level: ['-O0', '-O1', '-O2', '-O3']
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: sudo apt update
       - run: sudo apt install -y llvm-${{ matrix.llvm-version }}-dev clang-${{ matrix.llvm-version }} make
       - run: echo "LLVM_CONFIG=llvm-config-${{ matrix.llvm-version }}" >> $GITHUB_ENV
@@ -38,7 +38,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: sudo apt update
       - run: sudo apt install -y llvm-{14,15,16}-dev clang-{14,15,16} make
       - run: LLVM_CONFIG=llvm-config-14 ./doctest.sh
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index 5b8594f3..d1986f25 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -14,7 +14,7 @@ jobs:
         # Testing all levels because there was a bug that only happened with -O1. (#224)
         opt-level: ['-O0', '-O1', '-O2', '-O3']
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: brew install bash diffutils llvm@${{ matrix.llvm-version }}
       - name: "Select LLVM version"
         run: |
@@ -41,6 +41,6 @@ jobs:
     runs-on: macos-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: brew install bash diffutils llvm@15
       - run: ./doctest.sh
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 6513889c..a17a7abd 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: git fetch --tags
       - id: tagname
         run: |
diff --git a/.github/workflows/valgrind.yml b/.github/workflows/valgrind.yml
index 237ee123..11855df0 100644
--- a/.github/workflows/valgrind.yml
+++ b/.github/workflows/valgrind.yml
@@ -17,7 +17,7 @@ jobs:
         opt-level: ['-O0', '-O1', '-O2', '-O3']
       fail-fast: false
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # Do not valgrind when there's nothing new to valgrind in the repo
       - name: Check if there was any commits within the last 24 hours
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index fda43fbb..92c1e12a 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -69,7 +69,7 @@ jobs:
     runs-on: windows-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       # TODO: figure out why --small doesn't work here
       - run: source activate && ./windows_setup.sh
         shell: bash
@@ -142,7 +142,7 @@ jobs:
       - name: Display size of jou.zip
         run: ls -lh jou.zip
         shell: bash
-      - uses: actions/upload-artifact@v3
+      - uses: actions/upload-artifact@v4
         with:
           name: windows-zip
           path: jou.zip
@@ -151,7 +151,7 @@ jobs:
     runs-on: windows-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           # Add a space in the folder name to trigger bugs like #165
           path: "test dir"
@@ -171,7 +171,7 @@ jobs:
     runs-on: windows-latest
     timeout-minutes: 5
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: ./windows_setup.sh --small
         shell: bash
       - run: source activate && ./doctest.sh
@@ -182,10 +182,10 @@ jobs:
     runs-on: windows-latest
     timeout-minutes: 10
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           path: repo
-      - uses: actions/download-artifact@v3
+      - uses: actions/download-artifact@v4
         with:
           name: windows-zip
       - run: unzip jou.zip