Add workflow for updating Pixi lockfile via a pull request

Author: douglatornell

.github/workflows/pixi-lockfile-updater.yaml

@@ -0,0 +1,40 @@
+# Reusable workflow to run pixi-diff-to-markdown and create a PR with the updated lockfile.
+
+name: pixi-lockfile-updater
+
+on:
+  workflow_call:
+    secrets:
+      GITHUB_TOKEN:
+        required: true
+
+jobs:
+  pixi-update:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v6
+
+      - name: Set up Pixi
+        uses: prefix-dev/setup-pixi@1b2de7f3351f171c8b4dfeb558c639cb58ed4ec0
+        with:
+          run-install: false
+
+      - name: Update lockfile
+        run: |
+          set -o pipefail
+          pixi global install pixi-diff-to-markdown
+          pixi update --json | pixi exec pixi diff-to-markdown >> diff.md
+
+      - name: Create pull request
+        uses: peter-evans/create-pull-request@5f6978faf089d4d20b00c7766989d076bb2fc7f1
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          commit-message: Update pixi lockfile
+          title: Update pixi lockfile
+          body-path: diff.md
+          branch: update-pixi
+          base: main
+          labels: pixi
+          delete-branch: true
+          add-paths: pixi.lock

.github/workflows/update-pixi-lockfile.yaml

@@ -0,0 +1,20 @@
+# Updates the pixi lockfile and create a pull request containing the changes.
+
+name: update-pixi-lockfile
+
+on:
+  # Enable workflow to be triggered from GitHub CLI, browser, or via API
+  workflow_dispatch:
+
+  schedule:
+    - cron: 43 5 16 * *  # 05:43 UTC on the 16th day of each month
+
+jobs:
+  update-pixi-lockfile:
+    permissions:
+      contents: write
+      pull-requests: write
+
+    uses: UBC-MOAD/gha-workflows/.github/workflows/pixi-lockfile-updater.yaml@main
+    secrets:
+      GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

README.md

@@ -12,6 +12,11 @@ Reusable GitHub Actions workflows for MOAD repositories and workflow management
 
 ## Changes
 
+### 11-May-2026
+
+Added `update-pixi-lockfile.yaml` workflow to xxx.
+
+
 ### 31-Dec-2025
 
 Added [Pixi](https://pixi.sh/latest/) versions of `pytest-with-coverage` and `sphinx-linkcheck`
@@ -208,6 +213,33 @@ jobs:
 ```
 
 
+### `pixi-lockfile-updater`
+
+**Notes:**
+
+* Each repo should have a different cron schedule.
+  Please see https://salishseacast.slack.com/archives/C01GYJBSF0X/p1608574921004500
+
+```yaml
+name: update-pixi-lockfile
+
+on:
+  # Enable workflow to be triggered from GitHub CLI, browser, or via API
+  workflow_dispatch:
+
+  schedule:
+    - cron: 43 5 6 * *  # 05:43 UTC on the 6th day of each month
+
+jobs:
+  update-pixi-lockfile:
+    permissions:
+      contents: write
+      pull-requests: write
+
+    uses: UBC-MOAD/gha-workflows/.github/workflows/pixi-lockfile-updater.yaml@main
+```
+
+
 ## `gha_workflows_checker.py` Script
 
 Use the GitHub CLI tool to list GitHub Actions workflows in repositories with their