diff --git a/.github/workflows/pipeline.yml b/.github/workflows/pipeline.yml
index da2c6d09..7e706f37 100644
--- a/.github/workflows/pipeline.yml
+++ b/.github/workflows/pipeline.yml
@@ -26,7 +26,35 @@ jobs:
       - run: "scripts-dev/check_newsfragment.sh ${{ github.event.number }}"
 
   checks:
-    uses: "matrix-org/backend-meta/.github/workflows/python-poetry-ci.yml@v2"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: matrix-org/setup-python-poetry@v1
+        with:
+          install-project: false
+          python-version: 3.11
+
+      - name: Import order (isort)
+        run: poetry run isort --check --diff .
+
+      - name: Code style (black)
+        run: poetry run black --check --diff .
+
+      - name: Semantic checks (ruff)
+        # --quiet suppresses the update check.
+        run: poetry run ruff --quiet .
+
+      - name: Restore/persist mypy's cache
+        uses: actions/cache@v3
+        with:
+          path: |
+            .mypy_cache
+          key: mypy-cache-${{ github.context.sha }}
+          restore-keys: mypy-cache-
+
+      - name: Typechecking (mypy)
+        run: poetry run mypy
+
   packaging:
     uses: "matrix-org/backend-meta/.github/workflows/packaging.yml@v1"
 
diff --git a/changelog.d/580.misc b/changelog.d/580.misc
new file mode 100644
index 00000000..ba3c33cf
--- /dev/null
+++ b/changelog.d/580.misc
@@ -0,0 +1 @@
+Inline CI config and pin to python 3.11.