diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 7b37b50..6bf34d3 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -44,7 +44,7 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          python -m pip install .[test]
+          python -m pip install .[test,whoosh]
 
       - name: Test with pytest
         run: python -m pytest -vv --durations 25
diff --git a/pyproject.toml b/pyproject.toml
index c9c0fa2..edfdc1c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -116,9 +116,11 @@ enable_error_code = [
 
 [[tool.mypy.overrides]]
 module = [
+    "pytest",
     "sqlalchemy",
     "sqlalchemy.orm",
     "sqlalchemy.sql",
+    "sqlalchemy.sql.expression",
     "whoosh",
     "whoosh.analysis",
     "whoosh.fields",
diff --git a/sphinxcontrib/websupport/storage/sqlalchemy_db.py b/sphinxcontrib/websupport/storage/sqlalchemy_db.py
index e681a68..13e094e 100644
--- a/sphinxcontrib/websupport/storage/sqlalchemy_db.py
+++ b/sphinxcontrib/websupport/storage/sqlalchemy_db.py
@@ -5,10 +5,11 @@
 
 from __future__ import annotations
 
-from datetime import datetime, timezone
+from datetime import datetime
 
 from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String, Text
 from sqlalchemy.orm import aliased, declarative_base, relationship, sessionmaker
+from sqlalchemy.sql.expression import true
 
 Base = declarative_base()
 Session = sessionmaker()
@@ -51,7 +52,7 @@ def nested_comments(self, username, moderator):
 
         # Filter out all comments that are not moderated yet.
         if not moderator:
-            q = q.filter(Comment.displayed is True)
+            q = q.filter(Comment.displayed == true())
 
         # Retrieve all results. Results must be ordered by Comment.path
         # so that we can easily transform them from a flat list to a tree.
@@ -159,7 +160,7 @@ def serializable(self, vote=0):
         """Creates a serializable representation of the comment. This is
         converted to JSON, and used on the client side.
         """
-        delta = datetime.now(tz=timezone.utc) - self.time
+        delta = datetime.now() - self.time  # noqa: DTZ005
 
         time = {
             "year": self.time.year,
diff --git a/sphinxcontrib/websupport/storage/sqlalchemystorage.py b/sphinxcontrib/websupport/storage/sqlalchemystorage.py
index 070692b..b48c32f 100644
--- a/sphinxcontrib/websupport/storage/sqlalchemystorage.py
+++ b/sphinxcontrib/websupport/storage/sqlalchemystorage.py
@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from datetime import datetime, timezone
+from datetime import datetime
 
 import sqlalchemy
 from sqlalchemy.orm import aliased
@@ -72,7 +72,7 @@ def add_comment(self, text, displayed, username, time,
                 raise CommentNotAllowedError(msg)
 
         comment = Comment(text, displayed, username, 0,
-                          time or datetime.now(tz=timezone.utc), proposal, proposal_diff)
+                          time or datetime.now(), proposal, proposal_diff)  # noqa: DTZ005
         session.add(comment)
         session.flush()
         # We have to flush the session before setting the path so the
diff --git a/tests/conftest.py b/tests/conftest.py
index 3934d3f..dcdd12a 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -9,6 +9,6 @@
 )
 
 
-@pytest.fixture(scope='session')
+@pytest.fixture(scope='session')  # type: ignore[misc]
 def rootdir() -> Path:
     return Path(__file__).resolve().parent / 'roots'