diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..894f7ca
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,28 @@
+# Copyright 2026 Open Reaction Database Project Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Actions in .github/workflows are pinned to commit SHAs. Dependabot rewrites
+# both the SHA and its trailing version comment, which is what keeps a pinned
+# workflow from freezing on whatever was current the day it was written.
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+    groups:
+      # One pull request per month for all actions rather than one per action.
+      actions:
+        patterns:
+          - "*"
diff --git a/.github/workflows/checks.yml b/.github/workflows/checks.yml
index a4d694f..a8e9e3c 100644
--- a/.github/workflows/checks.yml
+++ b/.github/workflows/checks.yml
@@ -24,8 +24,8 @@ jobs:
   check_licenses:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-go@v5
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - uses: actions/setup-go@40f1582b2485089dde7abd97c1529aa768e1baff # v5
         with:
           go-version: '>=1.16'
       - name: Install addlicense
@@ -36,8 +36,8 @@ jobs:
   check_python:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v5
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - uses: astral-sh/setup-uv@d4b2f3b6ecc6e67c4457f6d3e41ec42d3d0fcb86 # v5
         with:
           enable-cache: true
           python-version: "3.12"
@@ -53,8 +53,8 @@ jobs:
   check_javascript:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
         with:
           node-version: '20'
           cache: 'npm'
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index eb00aff..584c205 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -30,8 +30,8 @@ jobs:
     env:
       PGDATA: $GITHUB_WORKSPACE/rdkit-postgres
     steps:
-      - uses: actions/checkout@v4
-      - uses: conda-incubator/setup-miniconda@v3
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - uses: conda-incubator/setup-miniconda@fc2d68f6413eb2d87b895e92f8584b5b94a10167 # v3
         with:
           miniconda-version: 'latest'
       - name: Setup PostgreSQL
@@ -40,12 +40,12 @@ jobs:
           # NOTE(skearnes): conda is only used for postgres (not python).
           conda install -c conda-forge rdkit-postgresql
           initdb
-      - uses: astral-sh/setup-uv@v5
+      - uses: astral-sh/setup-uv@d4b2f3b6ecc6e67c4457f6d3e41ec42d3d0fcb86 # v5
         with:
           enable-cache: true
           python-version: ${{ matrix.python-version }}
       - name: actions-setup-redis
-        uses: shogo82148/actions-setup-redis@v1.35.0
+        uses: shogo82148/actions-setup-redis@428a144f11914412a8f52902296e134dd2e0f925 # v1.35.0
       - name: Install ord_interface
         run: uv sync --frozen
       - name: Run tests
@@ -63,16 +63,16 @@ jobs:
     # NOTE(skearnes): ubuntu-latest AppArmor doesn't play nicely with puppeteer.
     runs-on: ubuntu-22.04
     steps:
-      - uses: actions/checkout@v4
-      - uses: astral-sh/setup-uv@v5
+      - uses: actions/checkout@11d5960a326750d5838078e36cf38b85af677262 # v4
+      - uses: astral-sh/setup-uv@d4b2f3b6ecc6e67c4457f6d3e41ec42d3d0fcb86 # v5
         with:
           enable-cache: true
           python-version: ${{ matrix.python-version }}
-      - uses: actions/setup-node@v4
+      - uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
       - name: actions-setup-redis
-        uses: shogo82148/actions-setup-redis@v1.35.0
+        uses: shogo82148/actions-setup-redis@428a144f11914412a8f52902296e134dd2e0f925 # v1.35.0
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v3
+        uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3
       - name: Install ord-interface
         run: uv sync --frozen
       - name: Install non-python test dependencies