diff --git a/bin/run_test.py b/bin/run_test.py
index 2fa1cbc5..95e76482 100755
--- a/bin/run_test.py
+++ b/bin/run_test.py
@@ -1,23 +1,10 @@
 #!/usr/bin/python
 
 from __future__ import print_function
-import os, sys, subprocess, shutil, json, argparse
+import os, sys, subprocess, shutil, json
 from glob import glob
 
-def main():
-    parser = argparse.ArgumentParser()
-    parser.add_argument("test_project_dir")
-    args = parser.parse_args()
-
-    test_project = os.path.abspath(args.test_project_dir)
-
-    # move cwd to the project root
-    os.chdir(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
-
-    if not os.path.exists(test_project):
-        print('No test project not found.', file=sys.stderr)
-        exit(2)
-
+def single_run(test_project):
     # load project settings into environment
     env_file = os.path.join(test_project, 'environment.json')
     project_env = {}
@@ -40,6 +27,22 @@ def main():
     # clean up
     shutil.rmtree('wheelhouse')
 
-    print('Project built successfully.')
+if __name__ == '__main__':
+    import argparse
 
-main()
+    parser = argparse.ArgumentParser()
+    parser.add_argument("test_project_dir")
+    args = parser.parse_args()
+
+    project_path = os.path.abspath(args.test_project_dir)
+
+    # move cwd to the project root
+    os.chdir(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+    if not os.path.exists(project_path):
+        print('No test project not found.', file=sys.stderr)
+        exit(2)
+
+    single_run(project_path)
+
+    print('Project built successfully.')
diff --git a/bin/run_tests.py b/bin/run_tests.py
index 2c8504af..98e5eb49 100755
--- a/bin/run_tests.py
+++ b/bin/run_tests.py
@@ -4,44 +4,27 @@ from __future__ import print_function
 import os, sys, subprocess, shutil, json
 from glob import glob
 
-# move cwd to the project root
-os.chdir(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+from . import run_test
 
-### run the unit tests
+if __name__ == '__main__':
+    # move cwd to the project root
+    os.chdir(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
 
-subprocess.check_call(['python', '-m', 'pytest', 'unit_test'])
+    ### run the unit tests
 
-### run the integration tests
+    subprocess.check_call(['python', '-m', 'pytest', 'unit_test'])
 
-test_projects = glob('test/??_*')
+    ### run the integration tests
 
-if len(test_projects) == 0:
-    print('No test projects found. Aborting.', file=sys.stderr)
-    exit(2)
+    test_projects = glob('test/??_*')
 
-print('Testing projects:', test_projects)
+    if len(test_projects) == 0:
+        print('No test projects found. Aborting.', file=sys.stderr)
+        exit(2)
 
-for project_path in test_projects:
-    # load project settings into environment
-    env_file = os.path.join(project_path, 'environment.json')
-    project_env = {}
-    if os.path.exists(env_file):
-        with open(env_file) as f:
-            project_env = json.load(f)
+    print('Testing projects:', test_projects)
 
-    # run the build
-    env = os.environ.copy()
-    project_env = {str(k): str(v) for k, v in project_env.items()} # unicode not allowed in env
-    env.update(project_env)
-    print('Building %s with environment %s' % (project_path, project_env))
-    subprocess.check_call(['cibuildwheel', project_path], env=env)
-    wheels = glob('wheelhouse/*.whl')
-    print('%s built successfully. %i wheels built.' % (project_path, len(wheels)))
+    for project_path in test_projects:
+        run_test.single_run(project_path)
 
-    # check some wheels were actually built
-    assert len(wheels) >= 4
-
-    # clean up
-    shutil.rmtree('wheelhouse')
-
-print('%d projects built successfully.' % len(test_projects))
+    print('%d projects built successfully.' % len(test_projects))