diff --git a/.github/workflows/build_documentation.yml b/.github/workflows/build_documentation.yml
index 09215d9d..04c94b92 100644
--- a/.github/workflows/build_documentation.yml
+++ b/.github/workflows/build_documentation.yml
@@ -12,12 +12,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout the branch
-        uses: actions/checkout@v2.3.1
+        uses: actions/checkout@28c7f3d2b5162b5ddd3dfd9a45aa55eaf396478b # v2.3.1
         with:
           persist-credentials: false
 
       - name: Set up Python 3.11
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@0f07f7f756721ebd886c2462646a35f78a8bc4de # v1.2.4
         with:
           python-version: 3.11
 
diff --git a/.github/workflows/interrogate.yml b/.github/workflows/interrogate.yml
index 67fb1aed..733e6123 100644
--- a/.github/workflows/interrogate.yml
+++ b/.github/workflows/interrogate.yml
@@ -13,10 +13,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Clone the reference repository
-      uses: actions/checkout@v3.5.2
+      uses: actions/checkout@8e5e7e5ab8b370d6c329ec480221332ada57f0ab # v3.5.2
 
     - name: Set up Python 3.10.6
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@7f4fc3e22c37d6ff65e88745f38bd3157c663f7c # v4.9.1
       with:
         python-version: '3.10.6'
 
diff --git a/.github/workflows/publish-to-pypi.yml b/.github/workflows/publish-to-pypi.yml
index 2290d9b6..36a20f6f 100644
--- a/.github/workflows/publish-to-pypi.yml
+++ b/.github/workflows/publish-to-pypi.yml
@@ -13,11 +13,11 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
       with:
         persist-credentials: false
     - name: Set up Python
-      uses: actions/setup-python@v5
+      uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
       with:
         python-version: "3.x"
     - name: Install pypa/build
@@ -29,7 +29,7 @@ jobs:
     - name: Build a binary wheel and a source tarball
       run: python3 -m build
     - name: Store the distribution packages
-      uses: actions/upload-artifact@v4
+      uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
       with:
         name: python-package-distributions
         path: dist/
@@ -49,12 +49,12 @@ jobs:
 
     steps:
     - name: Download all the dists
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
       with:
         name: python-package-distributions
         path: dist/
     - name: Publish distribution 📦 to PyPI
-      uses: pypa/gh-action-pypi-publish@release/v1
+      uses: pypa/gh-action-pypi-publish@cef221092ed1bacb1cc03d23a2d87d1d172e277b # v1.14.0
 
   publish-to-testpypi:
     name: Publish Python 🐍 distribution 📦 to TestPyPI
@@ -71,11 +71,11 @@ jobs:
 
     steps:
     - name: Download all the dists
-      uses: actions/download-artifact@v4
+      uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
       with:
         name: python-package-distributions
         path: dist/
     - name: Publish distribution 📦 to TestPyPI
-      uses: pypa/gh-action-pypi-publish@release/v1
+      uses: pypa/gh-action-pypi-publish@cef221092ed1bacb1cc03d23a2d87d1d172e277b # v1.14.0
       with:
         repository-url: https://test.pypi.org/legacy/
diff --git a/.github/workflows/publish_documentation.yml b/.github/workflows/publish_documentation.yml
index 995c45ad..3b21409d 100644
--- a/.github/workflows/publish_documentation.yml
+++ b/.github/workflows/publish_documentation.yml
@@ -17,12 +17,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout the branch
-        uses: actions/checkout@v2.3.1
+        uses: actions/checkout@28c7f3d2b5162b5ddd3dfd9a45aa55eaf396478b # v2.3.1
         with:
           persist-credentials: false
 
       - name: Set up Python 3.11
-        uses: actions/setup-python@v1
+        uses: actions/setup-python@0f07f7f756721ebd886c2462646a35f78a8bc4de # v1.2.4
         with:
           python-version: 3.11
 
@@ -32,7 +32,7 @@ jobs:
           sphinx-build -b html docs docs/build/html
           
       - name: Publish the documentation
-        uses: JamesIves/github-pages-deploy-action@3.6.2
+        uses: JamesIves/github-pages-deploy-action@e80c869f0057899fc2cd28819b5bbe9de890524a # 3.6.2
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           BRANCH: gh-pages
diff --git a/.github/workflows/run_tests.yml b/.github/workflows/run_tests.yml
index 4f19259b..81dc6ebe 100644
--- a/.github/workflows/run_tests.yml
+++ b/.github/workflows/run_tests.yml
@@ -20,10 +20,10 @@ jobs:
     name: ${{ matrix.os }} with Python ${{ matrix.python-version }}
     steps:
     - name: Clone the reference repository
-      uses: actions/checkout@v3.5.2
+      uses: actions/checkout@8e5e7e5ab8b370d6c329ec480221332ada57f0ab # v3.5.2
 
     - name: Set up Python ${{ matrix.python-version }}
-      uses: actions/setup-python@v4
+      uses: actions/setup-python@7f4fc3e22c37d6ff65e88745f38bd3157c663f7c # v4.9.1
       with:
         python-version: ${{ matrix.python-version }}