diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 2ee906e..ce66f91 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -16,15 +16,15 @@ jobs:
       matrix:
         python-version: ["3.9", "3.10", "3.11", "3.12"]
     steps:
-      - uses: actions/checkout@v7.0.0
-      - uses: actions/setup-python@v6.3.0
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1  # v6.3.0
         id: target-python
         with:
           python-version: "${{ matrix.python-version }}"
       # poetry >=2.3 requires Python >=3.10, so install it under a fixed
       # interpreter and target the matrix Python via `poetry env use`. This keeps
       # the project tested on every matrix version (including 3.9).
-      - uses: actions/setup-python@v6.3.0
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1  # v6.3.0
         with:
           python-version: "3.12"
       - run: |
@@ -40,5 +40,5 @@ jobs:
     container:
       image: semgrep/semgrep:1.138.0
     steps:
-      - uses: actions/checkout@v7.0.0
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
       - run: tools/semgrep
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 09307a8..5aa6bcb 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -13,8 +13,8 @@ jobs:
       id-token: write
       contents: write
     steps:
-      - uses: actions/checkout@v7.0.0
-      - uses: actions/setup-python@v6.3.0
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
+      - uses: actions/setup-python@ece7cb06caefa5fff74198d8649806c4678c61a1  # v6.3.0
         with:
           python-version: 3.12
       - run: |
@@ -22,4 +22,4 @@ jobs:
           poetry sync
           poetry build
       - name: Publish package distributions to PyPI
-        uses: pypa/gh-action-pypi-publish@release/v1
+        uses: pypa/gh-action-pypi-publish@dc37677b2e1c63e2034f94d8a5b11f265b73ba33  # v1.14.2