diff --git a/aslprep/tests/tests.py b/aslprep/tests/tests.py
index 92b1da20f..1972623c1 100644
--- a/aslprep/tests/tests.py
+++ b/aslprep/tests/tests.py
@@ -1,5 +1,28 @@
+# emacs: -*- mode: python; py-indent-offset: 4; indent-tabs-mode: nil -*-
+# vi: set ft=python sts=4 ts=4 sw=4 et:
+#
+# Copyright 2023 The NiPreps Developers <nipreps@gmail.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# We support and encourage derived works from this project, please read
+# about our expectations at
+#
+#     https://www.nipreps.org/community/licensing/
+#
 """Utilities and mocks for testing and documentation building."""
 import os
+import shutil
 from contextlib import contextmanager
 from pathlib import Path
 from tempfile import mkdtemp
@@ -23,15 +46,20 @@ def mock_config():
         if sectionname != "environment":
             section = getattr(config, sectionname)
             section.load(configs, init=False)
+    config.nipype.omp_nthreads = 1
     config.nipype.init()
     config.loggers.init()
     config.init_spaces()
 
     config.execution.work_dir = Path(mkdtemp())
     config.execution.bids_dir = Path(pkgrf("aslprep", "tests/data/ds000240")).absolute()
+    config.execution.aslprep_dir = Path(mkdtemp())
     config.execution.init()
 
     yield
 
+    shutil.rmtree(config.execution.work_dir)
+    shutil.rmtree(config.execution.aslprep_dir)
+
     if not _old_fs:
         del os.environ["FREESURFER_HOME"]