diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 639537ba..4373df59 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -42,6 +42,23 @@ jobs:
             - name: Run tests
               run: python -m tox -e flake8_5,flake8_6
 
+    slow_tests:
+        runs-on: ubuntu-latest
+        strategy:
+            fail-fast: false
+        steps:
+            - uses: actions/checkout@v3
+            - name: Set up Python 3.11
+              uses: actions/setup-python@v3
+              with:
+                  python-version: 3.11
+            - name: Install dependencies
+              run: |
+                  python -m pip install --upgrade pip setuptools tox
+                  python -m tox --notest --recreate -e flake8_6
+            - name: Run tests
+              run: python -m tox -e flake8_6 -- --onlyfuzz --no-cov -n auto
+
     release:
         runs-on: ubuntu-latest
         needs: [check, test]
diff --git a/tests/conftest.py b/tests/conftest.py
index 9e5a617e..c838e9a5 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -9,6 +9,9 @@ def pytest_addoption(parser: pytest.Parser):
     parser.addoption(
         "--runfuzz", action="store_true", default=False, help="run fuzz tests"
     )
+    parser.addoption(
+        "--onlyfuzz", action="store_true", default=False, help="only run fuzz tests"
+    )
     parser.addoption(
         "--generate-autofix",
         action="store_true",
@@ -32,6 +35,13 @@ def pytest_collection_modifyitems(config: pytest.Config, items: list[pytest.Item
     if config.getoption("--runfuzz"):
         # --runfuzz given in cli: do not skip fuzz tests
         return
+
+    if config.getoption("--onlyfuzz"):
+        for item in items.copy():
+            if "fuzz" not in item.keywords:
+                items.remove(item)
+        return
+
     skip_fuzz = pytest.mark.skip(reason="need --runfuzz option to run")
     for item in items:
         if "fuzz" in item.keywords:
diff --git a/tox.ini b/tox.ini
index e0846705..f2737d25 100644
--- a/tox.ini
+++ b/tox.ini
@@ -12,7 +12,7 @@ deps =
     flake8_5: flake8>=5.0,<6.0
     pytest
     pytest-cov
-    #pytest-xdist
+    pytest-xdist
     hypothesis
     hypothesmith
     trio