diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index b297185..99c29e1 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -13,10 +13,10 @@ jobs:
     if: ((github.event_name == 'push' && startsWith(github.ref, 'refs/tags')) || contains(github.event.pull_request.labels.*.name, 'Build wheels'))
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332  # v4.1.7
       with:
         fetch-depth: 0
-    - uses: actions/setup-python@v5
+    - uses: actions/setup-python@39cd14951b08e74b54015e9e001cdefcf80e669f  # v5.1.1
       with:
         python-version: 3.8
 
@@ -41,7 +41,7 @@ jobs:
 
     - name: Publish distribution 📦 to PyPI
       if: startsWith(github.ref, 'refs/tags')
-      uses: pypa/gh-action-pypi-publish@release/v1
+      uses: pypa/gh-action-pypi-publish@ec4db0b4ddc65acdf4bff5fa45ac92d78b56bdf0  # v1.9.0
       with:
         user: __token__
         password: ${{ secrets.pypi_password }}
diff --git a/.github/workflows/python-tests.yml b/.github/workflows/python-tests.yml
index 4ba7215..fa7844c 100644
--- a/.github/workflows/python-tests.yml
+++ b/.github/workflows/python-tests.yml
@@ -84,11 +84,11 @@ jobs:
             toxenv: py312-test-pytestdev-numpydev
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332  # v4.1.7
       with:
         fetch-depth: 0
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@39cd14951b08e74b54015e9e001cdefcf80e669f  # v5.1.1
       with:
         python-version: ${{ matrix.python-version }}
     - name: Install Tox