diff --git a/ixmp/tests/test_tutorials.py b/ixmp/tests/test_tutorials.py
index dc7cee6fb..6d82dc395 100644
--- a/ixmp/tests/test_tutorials.py
+++ b/ixmp/tests/test_tutorials.py
@@ -15,26 +15,23 @@
 FLAKY = pytest.mark.flaky(
     reruns=5,
     rerun_delay=2,
-    condition="GITHUB_ACTIONS" in os.environ and platform.system() == "Windows",
+    condition=GHA and platform.system() == "Windows",
     reason="Flaky; see iiasa/ixmp#543",
 )
 
 
+@pytest.fixture(scope="session")
 def default_args():
     """Default arguments for :func:`.run_notebook."""
-    if GHA:
-        # Use a longer timeout
-        return dict(timeout=30)
-    else:
-        return dict()
+    # Use a longer timeout for GHA
+    return dict(timeout=30) if GHA else dict()
 
 
 @FLAKY
 @pytest.mark.xdist_group(name=f"{group_base_name}-0")
-def test_py_transport(tutorial_path, tmp_path, tmp_env):
+def test_py_transport(tutorial_path, tmp_path, tmp_env, default_args):
     fname = tutorial_path / "transport" / "py_transport.ipynb"
-    args = default_args()
-    nb, errors = run_notebook(fname, tmp_path, tmp_env, **args)
+    nb, errors = run_notebook(fname, tmp_path, tmp_env, **default_args)
     assert errors == []
 
     # FIXME use get_cell_by_name instead of assuming cell count/order is fixed
@@ -42,10 +39,9 @@ def test_py_transport(tutorial_path, tmp_path, tmp_env):
 
 
 @pytest.mark.xdist_group(name=f"{group_base_name}-0")
-def test_py_transport_scenario(tutorial_path, tmp_path, tmp_env):
+def test_py_transport_scenario(tutorial_path, tmp_path, tmp_env, default_args):
     fname = tutorial_path / "transport" / "py_transport_scenario.ipynb"
-    args = default_args()
-    nb, errors = run_notebook(fname, tmp_path, tmp_env, **args)
+    nb, errors = run_notebook(fname, tmp_path, tmp_env, **default_args)
     assert errors == []
 
     assert np.isclose(get_cell_output(nb, "scen-z")["lvl"], 153.675)
@@ -56,24 +52,22 @@ def test_py_transport_scenario(tutorial_path, tmp_path, tmp_env):
 @pytest.mark.xdist_group(name=f"{group_base_name}-1")
 @pytest.mark.rixmp
 # TODO investigate and resolve the cause of the time outs; remove this mark
-@pytest.mark.skipif(
-    "GITHUB_ACTIONS" in os.environ and sys.platform == "linux", reason="Times out"
-)
-def test_R_transport(tutorial_path, tmp_path, tmp_env):
+@pytest.mark.skipif(GHA and sys.platform == "linux", reason="Times out")
+def test_R_transport(tutorial_path, tmp_path, tmp_env, default_args):
     fname = tutorial_path / "transport" / "R_transport.ipynb"
-    args = default_args()
-    nb, errors = run_notebook(fname, tmp_path, tmp_env, kernel_name="IR", **args)
+    nb, errors = run_notebook(
+        fname, tmp_path, tmp_env, kernel_name="IR", **default_args
+    )
     assert errors == []
 
 
 @pytest.mark.xdist_group(name=f"{group_base_name}-1")
 @pytest.mark.rixmp
 # TODO investigate and resolve the cause of the time outs; remove this mark
-@pytest.mark.skipif(
-    "GITHUB_ACTIONS" in os.environ and sys.platform == "linux", reason="Times out"
-)
-def test_R_transport_scenario(tutorial_path, tmp_path, tmp_env):
+@pytest.mark.skipif(GHA and sys.platform == "linux", reason="Times out")
+def test_R_transport_scenario(tutorial_path, tmp_path, tmp_env, default_args):
     fname = tutorial_path / "transport" / "R_transport_scenario.ipynb"
-    args = default_args()
-    nb, errors = run_notebook(fname, tmp_path, tmp_env, kernel_name="IR", **args)
+    nb, errors = run_notebook(
+        fname, tmp_path, tmp_env, kernel_name="IR", **default_args
+    )
     assert errors == []