diff --git a/.gitignore b/.gitignore
index e2f3010..70ca77b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,7 @@ dist
 
 .eggs
 .tox
+.coverage*
 .pytest_cache
 .idea
 
diff --git a/filetracker/servers/run.py b/filetracker/servers/run.py
index 30f4575..5ca8d61 100755
--- a/filetracker/servers/run.py
+++ b/filetracker/servers/run.py
@@ -80,7 +80,7 @@
 
 
 def strip_margin(text):
-    return re.sub('\n[ \t]*\|', '\n', text)
+    return re.sub(r'\n[ \t]*\|', '\n', text)
 
 
 def main(args=None):
diff --git a/filetracker/tests/interaction_test.py b/filetracker/tests/interaction_test.py
index 0e5affe..93e9c8b 100644
--- a/filetracker/tests/interaction_test.py
+++ b/filetracker/tests/interaction_test.py
@@ -172,11 +172,11 @@ def test_put_older_should_fail(self):
             self.client.get_stream('/older.txt@1')
 
     def test_get_nonexistent_should_404(self):
-        with self.assertRaisesRegexp(FiletrackerError, "404"):
+        with self.assertRaisesRegex(FiletrackerError, "404"):
             self.client.get_stream('/nonexistent.txt')
 
     def test_delete_nonexistent_should_404(self):
-        with self.assertRaisesRegexp(FiletrackerError, "404"):
+        with self.assertRaisesRegex(FiletrackerError, "404"):
             self.client.delete_file('/nonexistent.txt')
 
     def test_delete_should_remove_file_and_dir(self):
@@ -197,7 +197,7 @@ def test_delete_should_remove_file_and_dir(self):
                     ),
                 )
 
-        with self.assertRaisesRegexp(FiletrackerError, "404"):
+        with self.assertRaisesRegex(FiletrackerError, "404"):
             self.client.get_stream('/dir/del.txt')
 
 
diff --git a/filetracker/tests/migration_test.py b/filetracker/tests/migration_test.py
index a4d19af..a2e75a7 100644
--- a/filetracker/tests/migration_test.py
+++ b/filetracker/tests/migration_test.py
@@ -118,7 +118,7 @@ def test_file_version_should_return_version_from_fallback(self):
         )
 
     def test_file_version_of_not_existent_file_should_return_404(self):
-        with self.assertRaisesRegexp(FiletrackerError, "404"):
+        with self.assertRaisesRegex(FiletrackerError, "404"):
             self.client.get_stream('/nonexistent.txt')
 
 
diff --git a/tox.ini b/tox.ini
index f4503bc..6b54760 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,11 @@
 [tox]
-envlist=py27,py37
+envlist = py38,py39
 
 [testenv]
-deps=pytest
-     pytest-cov
+extras = server
+deps = pytest
+       pytest-cov
+setenv =
+# Needed for systems with an AGPL-licensed Berkeley DB
+         YES_I_HAVE_THE_RIGHT_TO_USE_THIS_BERKELEY_DB_VERSION = 1
 commands = pytest --cov=./ {posargs}