diff --git a/djtriggers/__init__.py b/djtriggers/__init__.py
index 503eeb9..cfb007c 100644
--- a/djtriggers/__init__.py
+++ b/djtriggers/__init__.py
@@ -1 +1 @@
-__version__ = '2.1.4'
+__version__ = '2.1.5'
diff --git a/djtriggers/tests/test_models.py b/djtriggers/tests/test_models.py
index 527c944..e6cc282 100644
--- a/djtriggers/tests/test_models.py
+++ b/djtriggers/tests/test_models.py
@@ -147,7 +147,7 @@ def test_process(self, mock_logger):
 
     @patch.object(TriggerLogger, 'log_result')
     def test_process_already_processed(self, mock_logger):
-        '''Reprocessing already processed triggers should just do nothing.'''
+        """Reprocessing already processed triggers should just do nothing."""
         trigger = DummyTriggerFactory(date_processed=timezone.now())
         assert trigger.date_processed is not None
         assert not mock_logger.called
diff --git a/requirements/requirements_test.txt b/requirements/requirements_test.txt
index 6ec2d8e..cff998d 100644
--- a/requirements/requirements_test.txt
+++ b/requirements/requirements_test.txt
@@ -20,32 +20,33 @@ requests==2.20.0
 
 
 # Flake8 checks for PEP-8 formatting and code quality
-flake8==3.3.0
-pycodestyle==2.3.1
+flake8==3.8.4
+entrypoints==0.3
+pycodestyle==2.6.0
 enum34==1.1.6
 configparser==3.5.0
-pyflakes==2.1.1
+pyflakes==2.2.0
 pep8==1.7.0
 # Checks for cyclomatic complexity
 mccabe==0.6.1
 # Checks for naming conventions
-pep8-naming==0.4.1
+pep8-naming==0.8.2
 # Checks for the use of print statements
-flake8-print==2.0.2
+flake8-print==3.1.0
 # Checks for the use of debug statements (pdb, ...)
-flake8-debugger==1.4.0
+flake8-debugger==3.1.0
 # Checks for things that should be comprehensions
-flake8-comprehensions==1.2.1
+flake8-comprehensions==2.1.0
 # Checks for non-existent mock methods
 flake8-mock==0.3
 # Checks for mutable function arguments
-flake8-mutable==1.1.0
+flake8-mutable==1.2.0
 # Checks for TODO statements (and similar)
 flake8-todo==0.7
 # Checks for uses of double quotes (without containing single quotes)
-flake8-quotes==0.9.0
+flake8-quotes==1.0.0
 # Checks for uses of old-style string formatting (using % instead of .format())
-flake8-pep3101==1.0
+flake8-pep3101==1.2.1
 # Checks for the overriding of builtins
 flake8-builtins-unleashed==1.3.1
 # Checks for uses of Django-style asserts
@@ -62,5 +63,5 @@ flake8-ugettext-alias==1.1
 flake8-user-model==1.1
 
 # StatsD allows us to push monitoring data to a Graphite server
-django-statsd-unleashed==1.0.1
-statsd==2.1.2
+django-statsd-unleashed==1.0.6
+statsd==3.2.1