diff --git a/pyproject.toml b/pyproject.toml
index f83e6963..ed139d0c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -41,6 +41,7 @@ enable_error_code = [
     "truthy-iterable",
     "ignore-without-code",
     "unused-awaitable",
+    "explicit-override",
 ]
 
 # Other options.
diff --git a/zulip/integrations/bridge_with_matrix/test_matrix.py b/zulip/integrations/bridge_with_matrix/test_matrix.py
index 0881fbe3..ca1488ae 100644
--- a/zulip/integrations/bridge_with_matrix/test_matrix.py
+++ b/zulip/integrations/bridge_with_matrix/test_matrix.py
@@ -9,6 +9,7 @@ from typing import Any, Awaitable, Callable, Iterator, List
 from unittest import TestCase, mock
 
 import nio
+from typing_extensions import override
 
 from .matrix_bridge import MatrixToZulip, ZulipToMatrix, read_configuration
 
@@ -183,6 +184,7 @@ class MatrixBridgeMatrixToZulipTests(TestCase):
     room = mock.MagicMock()
     room.user_name = lambda _: "John Smith"
 
+    @override
     def setUp(self) -> None:
         self.matrix_to_zulip = mock.MagicMock()
         self.matrix_to_zulip.get_message_content_from_event = (
@@ -229,6 +231,7 @@ class MatrixBridgeZulipToMatrixTests(TestCase):
         subject=valid_zulip_config["topic"],
     )
 
+    @override
     def setUp(self) -> None:
         self.zulip_to_matrix = mock.MagicMock()
         self.zulip_to_matrix.zulip_config = self.valid_zulip_config
diff --git a/zulip/integrations/rss/rss-bot b/zulip/integrations/rss/rss-bot
index 1cef95c0..4a592f1d 100755
--- a/zulip/integrations/rss/rss-bot
+++ b/zulip/integrations/rss/rss-bot
@@ -17,6 +17,7 @@ from html.parser import HTMLParser
 from typing import Any, Dict, List, Optional, Tuple
 
 import feedparser
+from typing_extensions import override
 
 import zulip
 
@@ -138,6 +139,7 @@ class MLStripper(HTMLParser):
         self.reset()
         self.fed: List[str] = []
 
+    @override
     def handle_data(self, data: str) -> None:
         self.fed.append(data)
 
diff --git a/zulip/integrations/zephyr/zephyr_ctypes.py b/zulip/integrations/zephyr/zephyr_ctypes.py
index 5817498b..d1fb9b4f 100644
--- a/zulip/integrations/zephyr/zephyr_ctypes.py
+++ b/zulip/integrations/zephyr/zephyr_ctypes.py
@@ -16,6 +16,8 @@ from ctypes import (
     c_void_p,
 )
 
+from typing_extensions import override
+
 libc = CDLL("libc.so.6")
 com_err = CDLL("libcom_err.so.2")
 libzephyr = CDLL("libzephyr.so.4")
@@ -198,6 +200,7 @@ class ZephyrError(Exception):
     def __init__(self, code: int) -> None:
         self.code = code
 
+    @override
     def __str__(self) -> str:
         return error_message(self.code).decode()
 
diff --git a/zulip/setup.py b/zulip/setup.py
index 9138338a..853908d2 100755
--- a/zulip/setup.py
+++ b/zulip/setup.py
@@ -67,7 +67,7 @@ setup(
         "requests[security]>=0.12.1",
         "distro",
         "click",
-        "typing_extensions>=3.7",
+        "typing_extensions>=4.5.0",
     ],
     packages=find_packages(exclude=["tests"]),
 )
diff --git a/zulip/zulip/__init__.py b/zulip/zulip/__init__.py
index 72508d12..c8074774 100644
--- a/zulip/zulip/__init__.py
+++ b/zulip/zulip/__init__.py
@@ -27,7 +27,7 @@ from typing import (
 
 import distro
 import requests
-from typing_extensions import Literal
+from typing_extensions import Literal, override
 
 __version__ = "0.8.2"
 
@@ -125,6 +125,7 @@ class CountingBackoff:
 
 
 class RandomExponentialBackoff(CountingBackoff):
+    @override
     def fail(self) -> None:
         super().fail()
         # Exponential growth with ratio sqrt(2); compute random delay
@@ -1802,6 +1803,7 @@ if LEGACY_CLIENT_INTERFACE_FROM_SERVER_DOCS_VERSION == "3":
     # This block is support for testing Zulip 3.x, which documents old
     # interfaces for the following functions:
     class LegacyInterfaceClient(Client):
+        @override
         def update_user_group_members(self, group_data: Dict[str, Any]) -> Dict[str, Any]:  # type: ignore[override] # Intentional override; see comments above.
             modern_group_data = group_data.copy()
             group_id = group_data["group_id"]
diff --git a/zulip_bots/setup.py b/zulip_bots/setup.py
index 3fe124a9..5a9cf984 100644
--- a/zulip_bots/setup.py
+++ b/zulip_bots/setup.py
@@ -57,7 +57,7 @@ setup(
         "html2text",
         "lxml",
         "BeautifulSoup4",
-        "typing_extensions",
+        "typing_extensions>=4.5.0",
         'importlib-metadata >= 3.6; python_version  < "3.10"',
     ],
     packages=find_packages(),
diff --git a/zulip_bots/zulip_bots/bots/baremetrics/test_baremetrics.py b/zulip_bots/zulip_bots/bots/baremetrics/test_baremetrics.py
index 6aeb6e22..792a6fa9 100644
--- a/zulip_bots/zulip_bots/bots/baremetrics/test_baremetrics.py
+++ b/zulip_bots/zulip_bots/bots/baremetrics/test_baremetrics.py
@@ -1,5 +1,7 @@
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.bots.baremetrics.baremetrics import BaremetricsHandler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -7,6 +9,7 @@ from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 class TestBaremetricsBot(BotTestCase, DefaultTests):
     bot_name = "baremetrics"
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info({"api_key": "TEST"}), patch("requests.get"):
             self.verify_reply("", "No Command Specified")
diff --git a/zulip_bots/zulip_bots/bots/chessbot/test_chessbot.py b/zulip_bots/zulip_bots/bots/chessbot/test_chessbot.py
index 03ff0578..336ee6e1 100644
--- a/zulip_bots/zulip_bots/bots/chessbot/test_chessbot.py
+++ b/zulip_bots/zulip_bots/bots/chessbot/test_chessbot.py
@@ -1,3 +1,5 @@
+from typing_extensions import override
+
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
 
@@ -107,6 +109,7 @@ To make your next move, respond to Chess Bot with
   h g f e d c b a
 ```"""
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info({"stockfish_location": "/foo/bar"}):
             response = self.get_response(dict(content=""))
diff --git a/zulip_bots/zulip_bots/bots/connect_four/test_connect_four.py b/zulip_bots/zulip_bots/bots/connect_four/test_connect_four.py
index 16491ccb..491b260c 100644
--- a/zulip_bots/zulip_bots/bots/connect_four/test_connect_four.py
+++ b/zulip_bots/zulip_bots/bots/connect_four/test_connect_four.py
@@ -1,5 +1,7 @@
 from typing import Dict, List
 
+from typing_extensions import override
+
 from zulip_bots.bots.connect_four.controller import ConnectFourModel
 from zulip_bots.game_handler import BadMoveException
 from zulip_bots.test_lib import BotTestCase, DefaultTests
@@ -8,6 +10,7 @@ from zulip_bots.test_lib import BotTestCase, DefaultTests
 class TestConnectFourBot(BotTestCase, DefaultTests):
     bot_name = "connect_four"
 
+    @override
     def make_request_message(
         self, content: str, user: str = "foo@example.com", user_name: str = "foo"
     ) -> Dict[str, str]:
diff --git a/zulip_bots/zulip_bots/bots/dialogflow/test_dialogflow.py b/zulip_bots/zulip_bots/bots/dialogflow/test_dialogflow.py
index 2a4246e4..4de7e6b7 100644
--- a/zulip_bots/zulip_bots/bots/dialogflow/test_dialogflow.py
+++ b/zulip_bots/zulip_bots/bots/dialogflow/test_dialogflow.py
@@ -3,6 +3,8 @@ from contextlib import contextmanager
 from typing import ByteString, Iterator
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.test_file_utils import read_bot_fixture_data
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
@@ -71,6 +73,7 @@ class TestDialogFlowBot(BotTestCase, DefaultTests):
     def test_alternate_response(self) -> None:
         self._test("test_alternate_result", "hello", "alternate result")
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info({"key": "abcdefg", "bot_info": "bot info foo bar"}):
             pass
diff --git a/zulip_bots/zulip_bots/bots/followup/test_followup.py b/zulip_bots/zulip_bots/bots/followup/test_followup.py
index 41d29cef..60767fc4 100755
--- a/zulip_bots/zulip_bots/bots/followup/test_followup.py
+++ b/zulip_bots/zulip_bots/bots/followup/test_followup.py
@@ -1,3 +1,5 @@
+from typing_extensions import override
+
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
 
@@ -30,6 +32,7 @@ class TestFollowUpBot(BotTestCase, DefaultTests):
         self.assertEqual(response["content"], "from foo@example.com: feed the cat")
         self.assertEqual(response["to"], "issue")
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         bot_response = (
             "Please specify the message you want to send to followup stream after @mention-bot"
diff --git a/zulip_bots/zulip_bots/bots/front/test_front.py b/zulip_bots/zulip_bots/bots/front/test_front.py
index 6c0e9ef3..f7a5c7af 100644
--- a/zulip_bots/zulip_bots/bots/front/test_front.py
+++ b/zulip_bots/zulip_bots/bots/front/test_front.py
@@ -1,11 +1,14 @@
 from typing import Any, Dict, Optional
 
+from typing_extensions import override
+
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
 
 class TestFrontBot(BotTestCase, DefaultTests):
     bot_name = "front"
 
+    @override
     def make_request_message(self, content: str) -> Dict[str, Any]:
         message = super().make_request_message(content)
         message["subject"] = "cnv_kqatm2"
@@ -18,6 +21,7 @@ class TestFrontBot(BotTestCase, DefaultTests):
             with self.assertRaises(KeyError):
                 bot, bot_handler = self._get_handlers()
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info({"api_key": "TEST"}):
             self.verify_reply("", "Unknown command. Use `help` for instructions.")
@@ -87,11 +91,13 @@ class TestFrontBot(BotTestCase, DefaultTests):
 class TestFrontBotWrongTopic(BotTestCase, DefaultTests):
     bot_name = "front"
 
+    @override
     def make_request_message(self, content: str) -> Dict[str, Any]:
         message = super().make_request_message(content)
         message["subject"] = "kqatm2"
         return message
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         pass
 
diff --git a/zulip_bots/zulip_bots/bots/game_handler_bot/test_game_handler_bot.py b/zulip_bots/zulip_bots/bots/game_handler_bot/test_game_handler_bot.py
index a437c654..de90052f 100644
--- a/zulip_bots/zulip_bots/bots/game_handler_bot/test_game_handler_bot.py
+++ b/zulip_bots/zulip_bots/bots/game_handler_bot/test_game_handler_bot.py
@@ -1,6 +1,8 @@
 from typing import Any, Dict, List
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.game_handler import GameInstance
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
@@ -8,6 +10,7 @@ from zulip_bots.test_lib import BotTestCase, DefaultTests
 class TestGameHandlerBot(BotTestCase, DefaultTests):
     bot_name = "game_handler_bot"
 
+    @override
     def make_request_message(
         self,
         content: str,
diff --git a/zulip_bots/zulip_bots/bots/giphy/test_giphy.py b/zulip_bots/zulip_bots/bots/giphy/test_giphy.py
index 7afa33df..173a2900 100755
--- a/zulip_bots/zulip_bots/bots/giphy/test_giphy.py
+++ b/zulip_bots/zulip_bots/bots/giphy/test_giphy.py
@@ -1,6 +1,7 @@
 from unittest.mock import patch
 
 from requests.exceptions import ConnectionError
+from typing_extensions import override
 
 from zulip_bots.test_file_utils import get_bot_message_handler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
@@ -10,6 +11,7 @@ class TestGiphyBot(BotTestCase, DefaultTests):
     bot_name = "giphy"
 
     # Test for bot response to empty message
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         bot_response = (
             "[Click to enlarge]"
diff --git a/zulip_bots/zulip_bots/bots/github_detail/test_github_detail.py b/zulip_bots/zulip_bots/bots/github_detail/test_github_detail.py
index d9a5331e..87778102 100755
--- a/zulip_bots/zulip_bots/bots/github_detail/test_github_detail.py
+++ b/zulip_bots/zulip_bots/bots/github_detail/test_github_detail.py
@@ -1,3 +1,5 @@
+from typing_extensions import override
+
 from zulip_bots.test_file_utils import get_bot_message_handler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -8,6 +10,7 @@ class TestGithubDetailBot(BotTestCase, DefaultTests):
     empty_config = {"owner": "", "repo": ""}
 
     # Overrides default test_bot_usage().
+    @override
     def test_bot_usage(self) -> None:
         bot = get_bot_message_handler(self.bot_name)
         bot_handler = StubBotHandler()
@@ -18,6 +21,7 @@ class TestGithubDetailBot(BotTestCase, DefaultTests):
         self.assertIn("displays details on github issues", bot.usage())
 
     # Override default function in BotTestCase
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info(self.mock_config):
             self.verify_reply("", "Failed to find any issue or PR.")
diff --git a/zulip_bots/zulip_bots/bots/idonethis/test_idonethis.py b/zulip_bots/zulip_bots/bots/idonethis/test_idonethis.py
index 9cdbc108..d714ab88 100644
--- a/zulip_bots/zulip_bots/bots/idonethis/test_idonethis.py
+++ b/zulip_bots/zulip_bots/bots/idonethis/test_idonethis.py
@@ -1,5 +1,7 @@
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
 
@@ -112,6 +114,7 @@ class TestIDoneThisBot(BotTestCase, DefaultTests):
                 "  * ID: 72c8241d2218464433268c5abd6625ac104e3d8f",
             )
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info(
             {"api_key": "12345678", "bot_info": "team"}
diff --git a/zulip_bots/zulip_bots/bots/link_shortener/test_link_shortener.py b/zulip_bots/zulip_bots/bots/link_shortener/test_link_shortener.py
index 01a6fd51..ea72bf05 100644
--- a/zulip_bots/zulip_bots/bots/link_shortener/test_link_shortener.py
+++ b/zulip_bots/zulip_bots/bots/link_shortener/test_link_shortener.py
@@ -1,5 +1,7 @@
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.bots.link_shortener.link_shortener import LinkShortenerHandler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -11,6 +13,7 @@ class TestLinkShortenerBot(BotTestCase, DefaultTests):
         with self.mock_config_info({"key": "qwertyuiop"}):
             self.verify_reply(message, response)
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with patch("requests.get"):
             self._test(
diff --git a/zulip_bots/zulip_bots/bots/mention/test_mention.py b/zulip_bots/zulip_bots/bots/mention/test_mention.py
index 5a9b5a42..16c799b8 100644
--- a/zulip_bots/zulip_bots/bots/mention/test_mention.py
+++ b/zulip_bots/zulip_bots/bots/mention/test_mention.py
@@ -1,5 +1,7 @@
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.bots.mention.mention import MentionHandler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -7,6 +9,7 @@ from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 class TestMentionBot(BotTestCase, DefaultTests):
     bot_name = "mention"
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info({"access_token": "12345"}), patch("requests.get"):
             self.verify_reply("", "Empty Mention Query")
diff --git a/zulip_bots/zulip_bots/bots/salesforce/test_salesforce.py b/zulip_bots/zulip_bots/bots/salesforce/test_salesforce.py
index 3dc33287..9e3b30be 100644
--- a/zulip_bots/zulip_bots/bots/salesforce/test_salesforce.py
+++ b/zulip_bots/zulip_bots/bots/salesforce/test_salesforce.py
@@ -3,6 +3,7 @@ from typing import Any, Dict, Iterator
 from unittest.mock import patch
 
 from simple_salesforce.exceptions import SalesforceAuthenticationFailed
+from typing_extensions import override
 
 from zulip_bots.test_file_utils import read_bot_fixture_data
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
@@ -111,6 +112,7 @@ class TestSalesforceBot(BotTestCase, DefaultTests):
         ), mock_salesforce_commands_types():
             bot, bot_handler = self._get_handlers()
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         self._test("test_one_result", "", help_text)
 
diff --git a/zulip_bots/zulip_bots/bots/tictactoe/tictactoe.py b/zulip_bots/zulip_bots/bots/tictactoe/tictactoe.py
index 32289642..b9e80744 100644
--- a/zulip_bots/zulip_bots/bots/tictactoe/tictactoe.py
+++ b/zulip_bots/zulip_bots/bots/tictactoe/tictactoe.py
@@ -2,6 +2,8 @@ import copy
 import random
 from typing import Any, List, Tuple
 
+from typing_extensions import override
+
 from zulip_bots.game_handler import BadMoveException, GameAdapter
 
 # -------------------------------------
@@ -267,6 +269,7 @@ class ticTacToeHandler(GameAdapter):
         "description": "Lets you play Tic-tac-toe against a computer.",
     }
 
+    @override
     def usage(self) -> str:
         return """
             You can play tic-tac-toe now! Make sure your
diff --git a/zulip_bots/zulip_bots/bots/trello/test_trello.py b/zulip_bots/zulip_bots/bots/trello/test_trello.py
index e2ea302f..9559a343 100644
--- a/zulip_bots/zulip_bots/bots/trello/test_trello.py
+++ b/zulip_bots/zulip_bots/bots/trello/test_trello.py
@@ -1,5 +1,7 @@
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.bots.trello.trello import TrelloHandler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -9,10 +11,12 @@ mock_config = {"api_key": "TEST", "access_token": "TEST", "user_name": "TEST"}
 class TestTrelloBot(BotTestCase, DefaultTests):
     bot_name: str = "trello"
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info(mock_config), patch("requests.get"):
             self.verify_reply("", "Empty Query")
 
+    @override
     def test_bot_usage(self) -> None:
         with self.mock_config_info(mock_config), patch("requests.get"):
             self.verify_reply(
diff --git a/zulip_bots/zulip_bots/bots/trivia_quiz/test_trivia_quiz.py b/zulip_bots/zulip_bots/bots/trivia_quiz/test_trivia_quiz.py
index e50c0363..9df9839d 100644
--- a/zulip_bots/zulip_bots/bots/trivia_quiz/test_trivia_quiz.py
+++ b/zulip_bots/zulip_bots/bots/trivia_quiz/test_trivia_quiz.py
@@ -3,6 +3,8 @@ import json
 from typing import Any, Dict, Optional, Tuple
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.bots.trivia_quiz.trivia_quiz import (
     fix_quotes,
     get_quiz_from_id,
@@ -41,6 +43,7 @@ class TestTriviaQuizBot(BotTestCase, DefaultTests):
         else:
             self.verify_reply(message, response)
 
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         self._test("", 'type "new" for a new question')
 
diff --git a/zulip_bots/zulip_bots/bots/weather/test_weather.py b/zulip_bots/zulip_bots/bots/weather/test_weather.py
index bd9d142f..ac23d141 100644
--- a/zulip_bots/zulip_bots/bots/weather/test_weather.py
+++ b/zulip_bots/zulip_bots/bots/weather/test_weather.py
@@ -1,6 +1,8 @@
 from typing import Optional
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
 
@@ -26,6 +28,7 @@ class TestWeatherBot(BotTestCase, DefaultTests):
                 self.verify_reply(message, response)
 
     # Override default function in BotTestCase
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with patch("requests.get"):
             self._test("", self.help_content)
diff --git a/zulip_bots/zulip_bots/bots/witai/test_witai.py b/zulip_bots/zulip_bots/bots/witai/test_witai.py
index 6ec202e0..a5c7a60e 100644
--- a/zulip_bots/zulip_bots/bots/witai/test_witai.py
+++ b/zulip_bots/zulip_bots/bots/witai/test_witai.py
@@ -1,6 +1,8 @@
 from typing import Any, Dict, Optional
 from unittest.mock import patch
 
+from typing_extensions import override
+
 from zulip_bots.test_file_utils import get_bot_message_handler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
 
@@ -28,6 +30,7 @@ class TestWitaiBot(BotTestCase, DefaultTests):
                     self.verify_reply("What is your favorite food?", "pizza")
 
     # This overrides the default one in `BotTestCase`.
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with patch("zulip_bots.bots.witai.witai.get_handle", return_value=mock_handle):
             with self.mock_config_info(self.MOCK_CONFIG_INFO):
diff --git a/zulip_bots/zulip_bots/bots/yoda/test_yoda.py b/zulip_bots/zulip_bots/bots/yoda/test_yoda.py
index b37696df..052291f7 100644
--- a/zulip_bots/zulip_bots/bots/yoda/test_yoda.py
+++ b/zulip_bots/zulip_bots/bots/yoda/test_yoda.py
@@ -1,5 +1,7 @@
 from typing import Optional
 
+from typing_extensions import override
+
 from zulip_bots.bots.yoda.yoda import ServiceUnavailableError
 from zulip_bots.test_lib import BotTestCase, DefaultTests
 
@@ -30,6 +32,7 @@ class TestYodaBot(BotTestCase, DefaultTests):
                 self.verify_reply(message, response)
 
     # Override default function in BotTestCase
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         self._test("", self.help_text)
 
diff --git a/zulip_bots/zulip_bots/bots/youtube/test_youtube.py b/zulip_bots/zulip_bots/bots/youtube/test_youtube.py
index 5373d7d1..d003d545 100644
--- a/zulip_bots/zulip_bots/bots/youtube/test_youtube.py
+++ b/zulip_bots/zulip_bots/bots/youtube/test_youtube.py
@@ -2,6 +2,7 @@ from typing import Dict
 from unittest.mock import patch
 
 from requests.exceptions import ConnectionError, HTTPError
+from typing_extensions import override
 
 from zulip_bots.test_file_utils import get_bot_message_handler
 from zulip_bots.test_lib import BotTestCase, DefaultTests, StubBotHandler
@@ -27,6 +28,7 @@ class TestYoutubeBot(BotTestCase, DefaultTests):
     )
 
     # Override default function in BotTestCase
+    @override
     def test_bot_responds_to_empty_message(self) -> None:
         with self.mock_config_info(self.normal_config), self.mock_http_conversation("test_keyok"):
             self.verify_reply("", self.help_content)
diff --git a/zulip_bots/zulip_bots/game_handler.py b/zulip_bots/zulip_bots/game_handler.py
index dc4a92d7..a3cacf5a 100644
--- a/zulip_bots/zulip_bots/game_handler.py
+++ b/zulip_bots/zulip_bots/game_handler.py
@@ -5,6 +5,8 @@ import re
 from copy import deepcopy
 from typing import Any, Dict, List, Tuple
 
+from typing_extensions import override
+
 from zulip_bots.lib import BotHandler
 
 
@@ -12,6 +14,7 @@ class BadMoveException(Exception):
     def __init__(self, message: str) -> None:
         self.message = message
 
+    @override
     def __str__(self) -> str:
         return self.message
 
@@ -20,6 +23,7 @@ class SamePlayerMove(Exception):
     def __init__(self, message: str) -> None:
         self.message = message
 
+    @override
     def __str__(self) -> str:
         return self.message
 
diff --git a/zulip_botserver/setup.py b/zulip_botserver/setup.py
index d606aaa2..49e27b42 100644
--- a/zulip_botserver/setup.py
+++ b/zulip_botserver/setup.py
@@ -44,6 +44,7 @@ setup(
         "zulip",
         "zulip_bots",
         "flask>=0.12.2",
+        "typing_extensions>=4.5.0",
     ],
     packages=find_packages(exclude=["tests"]),
 )
diff --git a/zulip_botserver/tests/server_test_lib.py b/zulip_botserver/tests/server_test_lib.py
index 8a1cb500..827b1c8e 100644
--- a/zulip_botserver/tests/server_test_lib.py
+++ b/zulip_botserver/tests/server_test_lib.py
@@ -3,10 +3,13 @@ import json
 from typing import Any, Dict, List, Optional
 from unittest import TestCase, mock
 
+from typing_extensions import override
+
 from zulip_botserver import server
 
 
 class BotServerTestCase(TestCase):
+    @override
     def setUp(self) -> None:
         server.app.testing = True
         self.app = server.app.test_client()
diff --git a/zulip_botserver/tests/test_server.py b/zulip_botserver/tests/test_server.py
index e6f25570..d01b2050 100644
--- a/zulip_botserver/tests/test_server.py
+++ b/zulip_botserver/tests/test_server.py
@@ -9,6 +9,7 @@ from typing import Any, Dict
 from unittest import mock
 
 import importlib_metadata as metadata
+from typing_extensions import override
 
 from zulip_bots.lib import BotHandler
 from zulip_botserver import server
@@ -26,6 +27,7 @@ class BotServerTests(BotServerTestCase):
         def handler_class(self) -> Any:
             return BotServerTests.MockMessageHandler()
 
+    @override
     def setUp(self) -> None:
         # Since initializing Client invokes `get_server_settings` that fails in the test
         # environment, we need to mock it to pretend that there exists a backend.