diff --git a/.travis.yml b/.travis.yml
index e45cc1c1..2b6d6665 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -6,6 +6,9 @@ matrix:
       env: TOXENV=py35
     - python: "3.6"
       env: TOXENV=py36
+    - os: linux
+      python: 3.8
+      env: TOXENV=py38
     - os: linux
       dist: xenial
       python: 3.7
diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index 5bb51160..66902a4a 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -59,4 +59,4 @@ jobs:
       pip install -U tox
     displayName: 'Install dependencies'
   - script: tox -e py
-    displayName: 'Run Tox'
\ No newline at end of file
+    displayName: 'Run Tox'
diff --git a/setup.cfg b/setup.cfg
index cc0025d9..5802826b 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -20,6 +20,7 @@ classifier =
     Programming Language :: Python :: 3.5
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
     Topic :: Software Development :: Testing
     Topic :: Software Development :: Quality Assurance
 project_urls =
diff --git a/stestr/repository/memory.py b/stestr/repository/memory.py
index 5bc31d83..2d60f00a 100644
--- a/stestr/repository/memory.py
+++ b/stestr/repository/memory.py
@@ -14,7 +14,6 @@
 
 from extras import try_import
 
-OrderedDict = try_import('collections.OrderedDict', dict)
 from io import BytesIO
 from operator import methodcaller
 
@@ -23,6 +22,8 @@
 
 from stestr.repository import abstract as repository
 
+OrderedDict = try_import('collections.OrderedDict', dict)
+
 
 class RepositoryFactory(repository.AbstractRepositoryFactory):
     """A factory that can initialise and open memory repositories.
@@ -152,8 +153,8 @@ def _handle_test(self, test_dict):
         duration_delta = stop - start
         duration_seconds = (
             (duration_delta.microseconds + (
-                duration_delta.seconds + duration_delta.days
-                * 24 * 3600) * 10 ** 6) / 10.0 ** 6)
+                duration_delta.seconds +
+                duration_delta.days * 24 * 3600) * 10 ** 6) / 10.0 ** 6)
         self._repository._times[test_dict['id']] = duration_seconds
 
     def stopTestRun(self):
diff --git a/stestr/scheduler.py b/stestr/scheduler.py
index b2280e50..60e01971 100644
--- a/stestr/scheduler.py
+++ b/stestr/scheduler.py
@@ -109,6 +109,9 @@ def partition_tests(test_ids, concurrency, repository, group_callback,
         :return: A list where each element is a distinct subset of test_ids,
             and the union of all the elements is equal to set(test_ids).
         """
+        def noop(_):
+            return None
+
         _group_callback = group_callback
         partitions = [list() for i in range(concurrency)]
         timed_partitions = [[0.0, partition] for partition in partitions]
@@ -123,7 +126,7 @@ def partition_tests(test_ids, concurrency, repository, group_callback,
         # Group tests: generate group_id -> test_ids.
         group_ids = collections.defaultdict(list)
         if _group_callback is None:
-            group_callback = lambda _: None
+            group_callback = noop
         else:
             group_callback = _group_callback
         for test_id in test_ids:
diff --git a/test-requirements.txt b/test-requirements.txt
index 4f6c1147..88b398e5 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -2,11 +2,11 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-hacking<0.12,>=0.11.0 # Apache-2.0
+hacking<1.2.0,>=1.1.0
 sphinx!=1.6.6,!=1.6.7,<2.0.0;python_version=='2.7'  # BSD
 sphinx!=1.6.6,!=1.6.7,!=2.1.0;python_version>='3.4'  # BSD
 mock>=2.0 # BSD
 subunit2sql>=1.8.0
 coverage>=4.0 # Apache-2.0
 ddt>=1.0.1 # MIT
-doc8>=0.8.0 # Apache-2.0
\ No newline at end of file
+doc8>=0.8.0 # Apache-2.0
diff --git a/tox.ini b/tox.ini
index 3af11eee..d4cdf3a9 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,6 +1,6 @@
 [tox]
 minversion = 1.6
-envlist = py37,py36,py35,py34,py27,pep8
+envlist = py38,py37,py36,py35,py34,py27,pep8
 skipsdist = True
 
 [testenv]