diff --git a/t/skip.py b/t/skip.py
new file mode 100644
index 0000000..c348385
--- /dev/null
+++ b/t/skip.py
@@ -0,0 +1,13 @@
+import sys
+
+import pytest
+
+if_win32 = pytest.mark.skipif(
+    sys.platform.startswith('win32'),
+    reason='Does not work on Windows'
+)
+
+unless_win32 = pytest.mark.skipif(
+    not sys.platform.startswith('win32'),
+    reason='Requires Windows to work'
+)

diff --git a/requirements/test.txt b/requirements/test.txt
index 71d9213..ad102df 100644
--- a/requirements/test.txt
+++ b/requirements/test.txt
@@ -1,4 +1,3 @@
-case>=1.3.1
 pytest<6.2
 # psutil is pinned since this is the last version that supports pypy2
 psutil==5.8.0
diff --git a/t/unit/test_common.py b/t/unit/test_common.py
index 2951342..df505e5 100644
--- a/t/unit/test_common.py
+++ b/t/unit/test_common.py
@@ -6,8 +6,9 @@ import signal
 
 from contextlib import contextmanager
 from time import time
+from unittest.mock import patch, Mock, call
 
-from case import Mock, call, patch, skip
+from t import skip
 
 from billiard.common import (
     _shutdown_cleanup,
diff --git a/t/unit/test_win32.py b/t/unit/test_win32.py
index 463bf07..4c4e287 100644
--- a/t/unit/test_win32.py
+++ b/t/unit/test_win32.py
@@ -3,10 +3,10 @@ from __future__ import absolute_import
 import pytest
 import signal
 
-from case import skip
 from billiard.util import set_pdeathsig, get_pdeathsig
 
 from billiard.compat import _winapi
+from t import skip
 
 
 @skip.unless_win32()

3.6.4.0: billiard still uses `nose` which is deprecated
https://nose.readthedocs.io/en/latest/
t/unit/test_common.py::test_reset_signals::test_shutdown_handler t/unit/test_common.py::test_reset_signals::test_does_not_reset_ignored_signal t/unit/test_common.py::test_reset_signals::test_does_not_reset_if_current_is_None t/unit/test_common.py::test_reset_signals::test_resets_for_SIG_DFL t/unit/test_common.py::test_reset_signals::test_resets_for_obj t/unit/test_common.py::test_reset_signals::test_handles_errors t/unit/test_common.py::test_restart_state::test_raises t/unit/test_common.py::test_restart_state::test_time_passed_resets_counter