diff --git a/tests/__init__.py b/tests/__init__.py
index e69de29..4cb17e9 100644
--- a/tests/__init__.py
+++ b/tests/__init__.py
@@ -0,0 +1,18 @@
+import sys
+import unittest
+
+
+def TestSuite():
+    suite = unittest.TestSuite()
+    loader = unittest.TestLoader()
+    if sys.platform == "win32":
+        from . import test_plat_win
+
+        suite.addTests(loader.loadTestsFromModule(test_plat_win))
+    else:
+        from . import test_script_main
+        from . import test_plat_other
+
+        suite.addTests(loader.loadTestsFromModule(test_script_main))
+        suite.addTests(loader.loadTestsFromModule(test_plat_other))
+    return suite
diff --git a/tox.ini b/tox.ini
index 2e76858..c23aca0 100644
--- a/tox.ini
+++ b/tox.ini
@@ -5,13 +5,19 @@ skip_missing_interpreters = True
 [testenv]
 platform = linux
 commands =
-    python setup.py test
+    python setup.py test --test-suite tests.TestSuite
 
 [testenv:py3-win]
 platform = win
 commands =
-    python setup.py test --test-suite tests.test_plat_win
+    python pip install pywin32
+    python setup.py test --test-suite tests.TestSuite
 
 [testenv:py27]
 deps =
     configparser
+
+[flake8]
+exclude = .tox,env,build
+max-line-length = 120
+ignore = E731,E203,E501,W503
\ No newline at end of file