diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 28e3678..9682985 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -36,27 +36,30 @@ jobs:
           platform: ubuntu-latest
         - python: "3.10"
           platform: ubuntu-latest
-        - python: pypy3.9
+        - python: pypy3.10
           platform: ubuntu-latest
     runs-on: ${{ matrix.platform }}
-    continue-on-error: ${{ matrix.python == '3.12' }}
+    continue-on-error: ${{ matrix.python == '3.13' }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Setup Python
         uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python }}
           allow-prereleases: true
       - name: Install tox
-        run: |
-          python -m pip install tox
+        run: python -m pip install tox
       - name: Run
         run: tox
 
-  diffcov:
+  collateral:
+    strategy:
+      fail-fast: false
+      matrix:
+        job: [diffcov, docs]
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
       - name: Setup Python
@@ -64,33 +67,16 @@ jobs:
         with:
           python-version: 3.x
       - name: Install tox
-        run: |
-          python -m pip install tox
-      - name: Evaluate coverage
-        run: tox
-        env:
-          TOXENV: diffcov
-
-  docs:
-    runs-on: ubuntu-latest
-    env:
-      TOXENV: docs
-    steps:
-      - uses: actions/checkout@v3
-      - name: Setup Python
-        uses: actions/setup-python@v4
-      - name: Install tox
-        run: |
-          python -m pip install tox
-      - name: Run
-        run: tox
+        run: python -m pip install tox
+      - name: Eval ${{ matrix.job }}
+        run: tox -e ${{ matrix.job }}
 
   check:  # This job does nothing and is only used for the branch protection
     if: always()
 
     needs:
     - test
-    - docs
+    - collateral
 
     runs-on: ubuntu-latest
 
@@ -109,14 +95,13 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Setup Python
         uses: actions/setup-python@v4
         with:
           python-version: 3.x
       - name: Install tox
-        run: |
-          python -m pip install tox
+        run: python -m pip install tox
       - name: Run
         run: tox -e release
         env:
diff --git a/pytest.ini b/pytest.ini
index 3f9dd5a..0a245bb 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -24,6 +24,9 @@ filterwarnings=
 	# pypa/build#615
 	ignore:'encoding' argument not specified::build.env
 
+	# dateutil/dateutil#1284
+	ignore:datetime.datetime.utcfromtimestamp:DeprecationWarning:dateutil.tz.tz
+
 	## end upstream
 
 	ignore:DictFilter is deprecated
diff --git a/tox.ini b/tox.ini
index 33da3de..331eeed 100644
--- a/tox.ini
+++ b/tox.ini
@@ -26,7 +26,9 @@ extras =
 changedir = docs
 commands =
 	python -m sphinx -W --keep-going . {toxinidir}/build/html
-	python -m sphinxlint
+	python -m sphinxlint \
+		# workaround for sphinx-contrib/sphinx-lint#83
+		--jobs 1
 
 [testenv:finalize]
 description = assemble changelog and tag a release