diff --git a/.github/workflows/announce-a-release.yml b/.github/workflows/announce-a-release.yml
index bbff508..42e3963 100644
--- a/.github/workflows/announce-a-release.yml
+++ b/.github/workflows/announce-a-release.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
@@ -43,7 +43,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
diff --git a/.github/workflows/breakage-against-ponyc-latest.yml b/.github/workflows/breakage-against-ponyc-latest.yml
index 9675e7a..b0e8669 100644
--- a/.github/workflows/breakage-against-ponyc-latest.yml
+++ b/.github/workflows/breakage-against-ponyc-latest.yml
@@ -11,7 +11,7 @@ jobs:
     container:
       image: ghcr.io/ponylang/shared-docker-ci-x86-64-unknown-linux-builder:latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Test
         run: make test config=debug
       - name: Send alert on failure
diff --git a/.github/workflows/generate-documentation.yml b/.github/workflows/generate-documentation.yml
index b3e1cce..3fc940d 100644
--- a/.github/workflows/generate-documentation.yml
+++ b/.github/workflows/generate-documentation.yml
@@ -24,7 +24,7 @@ jobs:
       image: ghcr.io/ponylang/library-documentation-action-v2-insiders:release
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
       - name: Generate documentation
         run: /entrypoint.py
         env:
diff --git a/.github/workflows/lint-action-workflows.yml b/.github/workflows/lint-action-workflows.yml
index 0bab4d8..e651731 100644
--- a/.github/workflows/lint-action-workflows.yml
+++ b/.github/workflows/lint-action-workflows.yml
@@ -12,7 +12,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
       - name: Check workflow files
         uses: docker://ghcr.io/ponylang/shared-docker-ci-actionlint:20230822
         with:
diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index fb95596..387825d 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -11,7 +11,7 @@ jobs:
     name: Lint bash, docker, markdown, and yaml
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Lint codebase
         uses: docker://github/super-linter:v3.8.3
         env:
@@ -28,7 +28,7 @@ jobs:
     container:
       image: ghcr.io/ponylang/changelog-tool:release
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Verify CHANGELOG
         run: changelog-tool verify
 
@@ -38,7 +38,7 @@ jobs:
     container:
       image: ghcr.io/ponylang/shared-docker-ci-x86-64-unknown-linux-builder:release
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Test
         run: make test config=debug
 
@@ -46,7 +46,7 @@ jobs:
     name: Test against recent ponyc release on x86-64 macOS
     runs-on: macos-13
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Install dependencies
         run: bash .ci-scripts/macOS-install-pony-tools.bash release
       - name: Test
@@ -58,7 +58,7 @@ jobs:
     name: Test against recent ponyc release on Windows
     runs-on: windows-2022
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
       - name: Test with most recent ponyc release
         run: |
           Invoke-WebRequest https://dl.cloudsmith.io/public/ponylang/releases/raw/versions/latest/ponyc-x86-64-pc-windows-msvc.zip -OutFile C:\ponyc.zip;
diff --git a/.github/workflows/prepare-for-a-release.yml b/.github/workflows/prepare-for-a-release.yml
index e9a7fae..b20ae67 100644
--- a/.github/workflows/prepare-for-a-release.yml
+++ b/.github/workflows/prepare-for-a-release.yml
@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
@@ -59,7 +59,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
@@ -84,7 +84,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 97ba6da..e6d4ccc 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -22,7 +22,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout main
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
@@ -43,7 +43,7 @@ jobs:
       image: ghcr.io/ponylang/library-documentation-action-v2-insiders:release
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}
@@ -69,7 +69,7 @@ jobs:
     needs:
       - generate-documentation
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4.1.1
         with:
           ref: "main"
           token: ${{ secrets.RELEASE_TOKEN }}