diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index d1849a15..581c9268 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -26,7 +26,7 @@ jobs:
             python-version: '3.12'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # - template: azure-templates/ccache.yml
       #   parameters:
@@ -36,7 +36,7 @@ jobs:
       #     pythonVersion: $(python.version)
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
           allow-prereleases: true
@@ -67,10 +67,10 @@ jobs:
         python-version: ['3.12', '3.11', '3.10', '3.9', '3.8']
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python from deadsnakes
-        uses: deadsnakes/action@v2.1.1
+        uses: deadsnakes/action@v2.1.1  # Upgrading will cause test failures.
         with:
           python-version: ${{ matrix.python-version }}
           debug: true
@@ -109,7 +109,7 @@ jobs:
             python-version: '3.12'
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # - template: azure-templates/ccache.yml
       #   parameters:
@@ -119,7 +119,7 @@ jobs:
       #     pythonVersion: $(python.version)
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
           allow-prereleases: true
@@ -163,10 +163,10 @@ jobs:
         python-version: ['3.9']
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -223,10 +223,10 @@ jobs:
         python-version: ['3.10']
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -248,7 +248,7 @@ jobs:
     name: Build documentation
     runs-on: 'ubuntu-latest'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # - template: azure-templates/python.yml
 
@@ -266,7 +266,7 @@ jobs:
           python -m sphinx -T -W -E -b html -d _build/doctrees -D language=en . _build/html
 
       - name: Upload built HTML files
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: hpy_html_docs
           path: docs/_build/html/*
@@ -277,7 +277,7 @@ jobs:
     name: C tests
     runs-on: 'ubuntu-latest'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - run: make -C c_test
 
 
@@ -285,12 +285,12 @@ jobs:
     name: Check autogen
     runs-on: 'ubuntu-latest'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
     # - template: azure-templates/python.yml
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           # autogen needs distutils
           python-version: '3.11'
@@ -323,7 +323,7 @@ jobs:
     name: Check Python 2.7 compatibility
     runs-on: 'ubuntu-20.04'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
     # - template: azure-templates/python.yml
     #   parameters:
@@ -354,10 +354,10 @@ jobs:
     runs-on: 'ubuntu-22.04'
     continue-on-error: true
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: '3.10'
 
@@ -372,12 +372,12 @@ jobs:
     name: Infer static analysis
     runs-on: 'ubuntu-latest'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       # - template: azure-templates/python.yml
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: '3.10'
 
@@ -399,10 +399,10 @@ jobs:
     name: Check micro benchmarks
     runs-on: 'ubuntu-latest'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Python
-        uses: actions/setup-python@v4
+        uses: actions/setup-python@v5
         with:
           python-version: '3.x'