diff --git a/.gitignore b/.gitignore
index 52fdcdc..252616a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -25,7 +25,7 @@ pip-log.txt
 .coverage
 .tox
 nosetests.xml
-.testrepository
+.stestr/
 .venv
 
 # Translations
diff --git a/.stestr.conf b/.stestr.conf
new file mode 100644
index 0000000..a072665
--- /dev/null
+++ b/.stestr.conf
@@ -0,0 +1,3 @@
+[DEFAULT]
+test_path=${OS_TEST_PATH:-./cloudpulse/tests/unit}
+top_dir=./
diff --git a/.zuul.yaml b/.zuul.yaml
index 1fd1fe4..9ba9187 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -2,6 +2,8 @@
     check:
       jobs:
         - openstack-tox-pep8
+        - openstack-tox-py36
     gate:
       jobs:
         - openstack-tox-pep8
+        - openstack-tox-py36
diff --git a/cloudpulse/TestManager/TestManager.py b/cloudpulse/TestManager/TestManager.py
index 69102a6..be8053a 100755
--- a/cloudpulse/TestManager/TestManager.py
+++ b/cloudpulse/TestManager/TestManager.py
@@ -100,7 +100,7 @@ class Periodic_TestManager(os_service.Service):
 
     def start(self):
         tasks = CONF.periodic_tests
-        for key in tasks.keys():
+        for key in list(tasks.keys()):
             interval, task_name = tasks[key], key
             if int(interval) > 0:
                 period_task = Periodic_Task(task_name)
diff --git a/cloudpulse/api/controllers/v1/utils.py b/cloudpulse/api/controllers/v1/utils.py
index 37fad67..c6c3d72 100644
--- a/cloudpulse/api/controllers/v1/utils.py
+++ b/cloudpulse/api/controllers/v1/utils.py
@@ -37,7 +37,10 @@ def validate_limit(limit):
     if limit is not None and limit <= 0:
         raise wsme.exc.ClientSideError(_("Limit must be positive"))
 
-    return min(CONF.api.max_limit, limit) or CONF.api.max_limit
+    if limit is not None:
+        return min(CONF.api.max_limit, limit)
+    else:
+        return CONF.api.max_limit
 
 
 def validate_sort_dir(sort_dir):
diff --git a/cloudpulse/api/middleware/auth_token.py b/cloudpulse/api/middleware/auth_token.py
index dad5260..114f0df 100644
--- a/cloudpulse/api/middleware/auth_token.py
+++ b/cloudpulse/api/middleware/auth_token.py
@@ -49,8 +49,8 @@ class AuthTokenMiddleware(auth_token.AuthProtocol):
         # The information whether the API call is being performed against the
         # public API is required for some other components. Saving it to the
         # WSGI environment is reasonable thereby.
-        env['is_public_api'] = any(map(lambda pattern: re.match(pattern, path),
-                                       self.public_api_routes))
+        env['is_public_api'] = any(
+            [re.match(pattern, path) for pattern in self.public_api_routes])
 
         if env['is_public_api']:
             return self._app(env, start_response)
diff --git a/cloudpulse/api/middleware/parsable_error.py b/cloudpulse/api/middleware/parsable_error.py
index 183666d..de0a010 100644
--- a/cloudpulse/api/middleware/parsable_error.py
+++ b/cloudpulse/api/middleware/parsable_error.py
@@ -18,9 +18,7 @@ response with one formatted so the client can parse it.
 Based on pecan.middleware.errordocument
 """
 
-import json
-# from xml import etree as et
-
+from oslo_serialization import jsonutils
 
 from cloudpulse.openstack.common._i18n import _
 
@@ -61,7 +59,8 @@ class ParsableErrorMiddleware(object):
 
         app_iter = self.app(environ, replacement_start_response)
         if (state['status_code'] // 100) not in (2, 3):
-            body = [json.dumps({'error_message': '\n'.join(app_iter)})]
+            body = [jsonutils.dump_as_bytes(
+                {'error_message': b'\n'.join(app_iter)})]
             state['headers'].append(('Content-Type', 'application/json'))
             state['headers'].append(('Content-Length', str(len(body[0]))))
         else:
diff --git a/cloudpulse/common/exception.py b/cloudpulse/common/exception.py
index f57e635..f04b682 100644
--- a/cloudpulse/common/exception.py
+++ b/cloudpulse/common/exception.py
@@ -200,7 +200,7 @@ class CloudpulseException(Exception):
             # kwargs doesn't match a variable in the message
             # log the issue and the kwargs
             LOG.exception(_LE('Exception in string format operation'))
-            for name, value in kwargs.iteritems():
+            for name, value in kwargs.items():
                 LOG.error(_LE("%(name)s: %(value)s") %
                           {'name': name, 'value': value})
             try:
diff --git a/cloudpulse/common/safe_utils.py b/cloudpulse/common/safe_utils.py
index 7f03fd6..4b33014 100644
--- a/cloudpulse/common/safe_utils.py
+++ b/cloudpulse/common/safe_utils.py
@@ -38,13 +38,13 @@ def getcallargs(function, *args, **kwargs):
     if 'self' in argnames[0] or 'cls' == argnames[0]:
         # The function may not actually be a method or have im_self.
         # Typically seen when it's stubbed with mox.
-        if inspect.ismethod(function) and hasattr(function, 'im_self'):
-            keyed_args[argnames[0]] = function.im_self
+        if inspect.ismethod(function) and hasattr(function, '__self__'):
+            keyed_args[argnames[0]] = function.__self__
         else:
             keyed_args[argnames[0]] = None
 
-    remaining_argnames = filter(lambda x: x not in keyed_args, argnames)
-    keyed_args.update(dict(zip(remaining_argnames, args)))
+    remaining_argnames = [x for x in argnames if x not in keyed_args]
+    keyed_args.update(dict(list(zip(remaining_argnames, args))))
 
     if defaults:
         num_defaults = len(defaults)
diff --git a/cloudpulse/common/timerthread.py b/cloudpulse/common/timerthread.py
index b3870a1..3f531f8 100755
--- a/cloudpulse/common/timerthread.py
+++ b/cloudpulse/common/timerthread.py
@@ -65,7 +65,7 @@ testthreads = []
 def delete_old_entries():
     tasks = CONF.periodic_tests
     num_tests = CONF.database.max_db_entries
-    num_range = len([key for key in tasks.keys() if int(tasks[key]) > 0])
+    num_range = len([key for key in list(tasks.keys()) if int(tasks[key]) > 0])
     conn = dbapi.get_backend()
     conn.delete_old_tests(num_range, num_tests)
 
diff --git a/cloudpulse/common/utils.py b/cloudpulse/common/utils.py
index 4c01645..93de932 100644
--- a/cloudpulse/common/utils.py
+++ b/cloudpulse/common/utils.py
@@ -26,7 +26,7 @@ import pecan
 import random
 import re
 import shutil
-import sys
+import six
 import tempfile
 import uuid
 
@@ -36,11 +36,6 @@ from oslo_config import cfg
 from oslo_utils import excutils
 import paramiko
 
-if sys.version_info.major == 3:
-    from past.builtins import basestring
-
-import six
-
 from cloudpulse.common import exception
 from cloudpulse.openstack.common._i18n import _
 from cloudpulse.openstack.common._i18n import _LE
@@ -376,14 +371,14 @@ def temporary_mutation(obj, **kwargs):
     NOT_PRESENT = object()
 
     old_values = {}
-    for attr, new_value in kwargs.items():
+    for attr, new_value in list(kwargs.items()):
         old_values[attr] = get(obj, attr, NOT_PRESENT)
         set_value(obj, attr, new_value)
 
     try:
         yield
     finally:
-        for attr, old_value in old_values.items():
+        for attr, old_value in list(old_values.items()):
             if old_value is NOT_PRESENT:
                 delete(obj, attr)
             else:
@@ -582,7 +577,7 @@ def allow_logical_names():
 def raise_exception_invalid_scheme(url):
     valid_schemes = ['http', 'https']
 
-    if not isinstance(url, basestring):
+    if not isinstance(url, str):
         raise exception.Urllib2InvalidScheme(url=url)
 
     scheme = url.split(':')[0]
diff --git a/cloudpulse/conductor/cpulse_lock.py b/cloudpulse/conductor/cpulse_lock.py
index 1b1ac69..2577a6d 100644
--- a/cloudpulse/conductor/cpulse_lock.py
+++ b/cloudpulse/conductor/cpulse_lock.py
@@ -16,9 +16,6 @@ from cloudpulse import objects
 import contextlib
 from oslo_log import log as logging
 from oslo_utils import excutils
-import sys
-if sys.version_info.major == 3:
-    from past.builtins import xrange
 import time
 
 LOG = logging.getLogger(__name__)
@@ -31,7 +28,7 @@ class CpulseLock(object):
         self.conductor_id = conductor_id
 
     def acquire(self, retry=True, times=10):
-        for num in xrange(0, times):
+        for num in range(0, times):
             lock_id = objects.CpulseLock.create(self.cpulse_test.name,
                                                 self.conductor_id)
             if lock_id is None:
diff --git a/cloudpulse/openstack/common/cliutils.py b/cloudpulse/openstack/common/cliutils.py
index a41eeba..49f370b 100644
--- a/cloudpulse/openstack/common/cliutils.py
+++ b/cloudpulse/openstack/common/cliutils.py
@@ -16,7 +16,7 @@
 # W0621: Redefining name %s from outer scope
 # pylint: disable=W0603,W0621
 
-from __future__ import print_function
+
 
 import getpass
 import inspect
diff --git a/cloudpulse/openstack/common/eventlet_backdoor.py b/cloudpulse/openstack/common/eventlet_backdoor.py
index b89f844..a97ddfd 100644
--- a/cloudpulse/openstack/common/eventlet_backdoor.py
+++ b/cloudpulse/openstack/common/eventlet_backdoor.py
@@ -14,7 +14,7 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from __future__ import print_function
+
 
 import copy
 import errno
@@ -80,7 +80,7 @@ def _print_greenthreads():
 
 
 def _print_nativethreads():
-    for threadId, stack in sys._current_frames().items():
+    for threadId, stack in list(sys._current_frames().items()):
         print(threadId)
         traceback.print_stack(stack)
         print()
diff --git a/cloudpulse/openstack/common/log.py b/cloudpulse/openstack/common/log.py
index 51b3d19..6436037 100644
--- a/cloudpulse/openstack/common/log.py
+++ b/cloudpulse/openstack/common/log.py
@@ -457,7 +457,7 @@ def _find_facility_from_conf():
         facility = facility_names.get(CONF.syslog_log_facility)
 
     if facility is None:
-        valid_facilities = facility_names.keys()
+        valid_facilities = list(facility_names.keys())
         consts = ['LOG_AUTH', 'LOG_AUTHPRIV', 'LOG_CRON', 'LOG_DAEMON',
                   'LOG_FTP', 'LOG_KERN', 'LOG_LPR', 'LOG_MAIL', 'LOG_NEWS',
                   'LOG_AUTH', 'LOG_SYSLOG', 'LOG_USER', 'LOG_UUCP',
@@ -659,7 +659,7 @@ class ContextFormatter(logging.Formatter):
         context = getattr(local.store, 'context', None)
         if context:
             d = _dictify_context(context)
-            for k, v in d.items():
+            for k, v in list(d.items()):
                 setattr(record, k, v)
 
         # NOTE(sdague): default the fancier formatting params
diff --git a/cloudpulse/openstack/common/periodic_task.py b/cloudpulse/openstack/common/periodic_task.py
index e9d0bed..2a28d3a 100644
--- a/cloudpulse/openstack/common/periodic_task.py
+++ b/cloudpulse/openstack/common/periodic_task.py
@@ -156,7 +156,7 @@ class _PeriodicTasksMeta(type):
         except AttributeError:
             cls._periodic_spacing = {}
 
-        for value in cls.__dict__.values():
+        for value in list(cls.__dict__.values()):
             if getattr(value, '_periodic_task', False):
                 cls._add_periodic_task(value)
 
diff --git a/cloudpulse/openstack/common/service.py b/cloudpulse/openstack/common/service.py
index 82be17a..70247ea 100644
--- a/cloudpulse/openstack/common/service.py
+++ b/cloudpulse/openstack/common/service.py
@@ -391,7 +391,7 @@ class ProcessLauncher(object):
 
                 cfg.CONF.reload_config_files()
                 for service in set(
-                        [wrap.service for wrap in self.children.values()]):
+                        [wrap.service for wrap in list(self.children.values())]):
                     service.reset()
 
                 for pid in self.children:
diff --git a/cloudpulse/operator/ansible/openstack_config_reader.py b/cloudpulse/operator/ansible/openstack_config_reader.py
index cb27b29..6be0527 100644
--- a/cloudpulse/operator/ansible/openstack_config_reader.py
+++ b/cloudpulse/operator/ansible/openstack_config_reader.py
@@ -12,7 +12,7 @@
 # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 # License for the specific language governing permissions and limitations
 # under the License.
-from hostObj import HostObject
+from cloudpulse.operator.ansible.hostObj import HostObject
 import os
 import yaml
 
@@ -39,7 +39,7 @@ class os_cfg_reader(object):
 
     def setOpenstackNodeIp(self):
         # print self.hostYamlObj
-        for key in self.hostYamlObj.keys():
+        for key in list(self.hostYamlObj.keys()):
             name = key
             ip = self.hostYamlObj[key]["ip"]
             hostname = key
@@ -81,8 +81,8 @@ class os_cfg_reader(object):
                 obj.getPassword())
             f.write('\n')
         f.close()
-"""
 
+    """
     def update_ansible_playbook(self):
         f = open('testcase-configs/ansible-playbook.yaml')
         f1 = open('testcase-configs/ansible-playbook_update.yaml', "w")
@@ -93,7 +93,7 @@ class os_cfg_reader(object):
                 f1.write(line)
         f.close()
         f1.close()
-"""
+    """
 if __name__ == '__main__':
     yhp = os_cfg_reader()
     yhp.setOpenstackNodeIp()
diff --git a/cloudpulse/operator/ansible/openstack_node_info_reader.py b/cloudpulse/operator/ansible/openstack_node_info_reader.py
index fdd820c..bf2cf5f 100644
--- a/cloudpulse/operator/ansible/openstack_node_info_reader.py
+++ b/cloudpulse/operator/ansible/openstack_node_info_reader.py
@@ -13,8 +13,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from __future__ import print_function
-from openstack_node import openstack_node_obj
+from cloudpulse.operator.ansible.openstack_node import openstack_node_obj
 import yaml
 
 
@@ -35,7 +34,7 @@ class openstack_node_info_reader(object):
 
     def get_host_list(self):
         openstack_host_list = []
-        for key in self.hostYamlObj.keys():
+        for key in list(self.hostYamlObj.keys()):
             name = key
             ip = self.hostYamlObj[key]["ip"]
             hostname = key
@@ -60,8 +59,8 @@ class openstack_node_info_reader(object):
     def get_galera_details(self):
         galera = {}
         print(self.hostYamlObj)
-        for key in self.hostYamlObj.keys():
-            if 'galerauser' in self.hostYamlObj[key].keys():
+        for key in list(self.hostYamlObj.keys()):
+            if 'galerauser' in list(self.hostYamlObj[key].keys()):
 
                 galera['username'] = self.hostYamlObj[key]['galerauser']
                 galera['password'] = self.hostYamlObj[key]['galerapassword']
diff --git a/cloudpulse/scenario/plugins/operator_tests/operator.py b/cloudpulse/scenario/plugins/operator_tests/operator.py
index 26d94f7..e9b1f40 100644
--- a/cloudpulse/scenario/plugins/operator_tests/operator.py
+++ b/cloudpulse/scenario/plugins/operator_tests/operator.py
@@ -10,7 +10,7 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
-from __future__ import print_function
+
 from cloudpulse.openstack.api import keystone_session
 from cloudpulse.openstack.api.nova_api import NovaHealth
 from cloudpulse.operator.ansible.openstack_node_info_reader import \
@@ -272,7 +272,7 @@ class operator_scenario(base.Scenario):
         docker_failed = ""
 
         res['output'] = res['output'].split('\n')
-        output = filter(lambda x: not re.match(r'^\s*$', x), res['output'])
+        output = [x for x in res['output'] if not re.match(r'^\s*$', x)]
 
         for line in output:
             line = line.split('|')
@@ -348,7 +348,7 @@ class operator_scenario(base.Scenario):
                 # Handle ceph status in luminous, result should be picked form
                 # 'status' instead of 'overall_status'
                 if len(ceph_json['health']['summary']) and \
-                        'summary' in ceph_json['health']['summary'][0].keys() \
+                        'summary' in list(ceph_json['health']['summary'][0].keys()) \
                         and 'mon health preluminous compat warning' in \
                         ceph_json['health']['summary'][0]['summary']:
                     overall_status = ceph_json['health']['status']
diff --git a/cloudpulse/tests/base.py b/cloudpulse/tests/base.py
index 0218093..d009088 100644
--- a/cloudpulse/tests/base.py
+++ b/cloudpulse/tests/base.py
@@ -88,7 +88,7 @@ class TestCase(base.BaseTestCase):
     def config(self, **kw):
         """Override config options for a test."""
         group = kw.pop('group', None)
-        for k, v in kw.iteritems():
+        for k, v in kw.items():
             CONF.set_override(k, v, group)
 
     def path_get(self, project_file=None):
diff --git a/cloudpulse/tests/fakes.py b/cloudpulse/tests/fakes.py
index 1a92773..e85350a 100644
--- a/cloudpulse/tests/fakes.py
+++ b/cloudpulse/tests/fakes.py
@@ -12,14 +12,14 @@
 
 import mock
 
-fakeAuthTokenHeaders = {'X-User-Id': u'773a902f022949619b5c2f32cd89d419',
-                        'X-Roles': u'admin, ResellerAdmin, _member_',
-                        'X-Project-Id': u'5588aebbcdc24e17a061595f80574376',
+fakeAuthTokenHeaders = {'X-User-Id': '773a902f022949619b5c2f32cd89d419',
+                        'X-Roles': 'admin, ResellerAdmin, _member_',
+                        'X-Project-Id': '5588aebbcdc24e17a061595f80574376',
                         'X-Project-Name': 'test',
                         'X-User-Name': 'test',
-                        'X-Auth-Token': u'5588aebbcdc24e17a061595f80574376',
-                        'X-Forwarded-For': u'10.10.10.10, 11.11.11.11',
-                        'X-Service-Catalog': u'{test: 12345}',
+                        'X-Auth-Token': '5588aebbcdc24e17a061595f80574376',
+                        'X-Forwarded-For': '10.10.10.10, 11.11.11.11',
+                        'X-Service-Catalog': '{test: 12345}',
                         'X-Auth-Url': 'fake_auth_url',
                         'X-Identity-Status': 'Confirmed',
                         'X-User-Domain-Name': 'domain',
diff --git a/cloudpulse/tests/unit/api/test_hooks.py b/cloudpulse/tests/unit/api/test_hooks.py
index 25b01bb..eabd90c 100644
--- a/cloudpulse/tests/unit/api/test_hooks.py
+++ b/cloudpulse/tests/unit/api/test_hooks.py
@@ -66,11 +66,11 @@ class TestContextHook(base.TestCase):
 
 class TestNoExceptionTracebackHook(api_base.FunctionalTest):
 
-    TRACE = [u'Traceback (most recent call last):',
-             u'  File "/opt/stack/cloudpulse/cloudpulse/openstack',
-             u'/common/rpc/amqp.py",',
+    TRACE = ['Traceback (most recent call last):',
+             '  File "/opt/stack/cloudpulse/cloudpulse/openstack',
+             '/common/rpc/amqp.py",',
              ' line 434, in _process_data\\n   **args)',
-             u'  File "/opt/stack/cloudpulse/cloudpulse/openstack/common/rpc/'
+             '  File "/opt/stack/cloudpulse/cloudpulse/openstack/common/rpc/'
              'dispatcher.py", line 172, in dispatch\\n   result ='
              ' getattr(proxyobj, method)(context, **kwargs)']
     MSG_WITHOUT_TRACE = "Test exception message."
@@ -103,7 +103,7 @@ class TestNoExceptionTracebackHook(api_base.FunctionalTest):
         # rare thing (happens due to wrong deserialization settings etc.)
         # we don't care about this garbage.
         expected_msg = ("Remote error: %s %s"
-                        % (test_exc_type, self.MSG_WITHOUT_TRACE) + "\n[u'")
+                        % (test_exc_type, self.MSG_WITHOUT_TRACE) + "\n['")
         actual_msg = json.loads(response.json['error_message'])['faultstring']
         self.assertEqual(expected_msg, actual_msg)
 
diff --git a/doc/source/conf.py b/doc/source/conf.py
index e1f37dc..8bfd86f 100755
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -37,8 +37,8 @@ source_suffix = '.rst'
 master_doc = 'index'
 
 # General information about the project.
-project = u'cloudpulse'
-copyright = u'2013, OpenStack Foundation'
+project = 'cloudpulse'
+copyright = '2013, OpenStack Foundation'
 
 # If true, '()' will be appended to :func: etc. cross-reference text.
 add_function_parentheses = True
@@ -67,8 +67,8 @@ htmlhelp_basename = '%sdoc' % project
 latex_documents = [
     ('index',
      '%s.tex' % project,
-     u'%s Documentation' % project,
-     u'OpenStack Foundation', 'manual'),
+     '%s Documentation' % project,
+     'OpenStack Foundation', 'manual'),
 ]
 
 # Example configuration for intersphinx: refer to the Python standard library.
diff --git a/setup.cfg b/setup.cfg
index f621136..92306da 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -7,20 +7,19 @@ author = OpenStack
 author-email = openstack-dev@lists.openstack.org
 home-page = https://git.openstack.org/cgit/openstack/cloudpulse
 classifier =
-	Environment :: OpenStack
-	Intended Audience :: Information Technology
-	Intended Audience :: System Administrators
-	License :: OSI Approved :: Apache Software License
-	Operating System :: POSIX :: Linux
-	Programming Language :: Python
-	Programming Language :: Python :: 2
-	Programming Language :: Python :: 2.7
-	Programming Language :: Python :: 3
-	Programming Language :: Python :: 3.3
-	
+        Environment :: OpenStack
+        Intended Audience :: Information Technology
+        Intended Audience :: System Administrators
+        License :: OSI Approved :: Apache Software License
+        Operating System :: POSIX :: Linux
+        Programming Language :: Python
+        Programming Language :: Python :: 3
+        Programming Language :: Python :: 3.6
+        Programming Language :: Python :: 3.7
+
 [files]
 packages =
-	cloudpulse
+        cloudpulse
 
 [build_sphinx]
 source-dir = doc/source
@@ -29,7 +28,7 @@ all_files = 1
 
 [entry_points]
 console_scripts =
-	cloudpulse-server = cloudpulse.cmd.api:main
+        cloudpulse-server = cloudpulse.cmd.api:main
 oslo.config.opts =
     cloudpulse = cloudpulse.opts:list_opts
 
diff --git a/test-requirements.txt b/test-requirements.txt
index af37363..283be04 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -8,9 +8,10 @@ bandit>=0.13.2
 coverage>=3.6
 discover
 python-subunit>=0.0.18
-sphinx>=1.1.2,!=1.2.0,!=1.3b1,<1.3
+sphinx!=1.6.6,!=1.6.7,!=2.1.0,!=3.0.0
 oslosphinx>=2.5.0  # Apache-2.0
 oslotest>=1.10.0  # Apache-2.0
-testrepository>=0.0.18
+stestr>=2.0.0
 testscenarios>=0.4
 testtools>=1.4.0
+mock==3.0.5
diff --git a/tox.ini b/tox.ini
index aeb5975..3aa2414 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
-minversion = 2.0
-envlist = pep8
+minversion = 3.1.1
+envlist = py36,pep8
 skipsdist = True
 
 [testenv]
@@ -16,11 +16,13 @@ deps =
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/test-requirements.txt
 passenv = TEMPEST_* OS_TEST_*
+whitelist_externals = find, stestr
 commands =
   find . -type f -name "*.py[c|o]" -delete
   stestr run {posargs}
 
 [testenv:pep8]
+whitelist_externals = bash
 commands =
   bash tools/flake8wrap.sh {posargs}