diff --git a/tests/briar/api/models/test_contacts.py b/tests/briar/api/models/test_contacts.py
index b3498fe98cd36b38b431dbd952ac8d64641ecda4..70f35c99193ac120131deb2ffed2fb116ee0c2aa 100644
--- a/tests/briar/api/models/test_contacts.py
+++ b/tests/briar/api/models/test_contacts.py
@@ -3,39 +3,42 @@
 # License-Filename: LICENSE.md
 
 import json
+from random import choices
 import requests_mock
-from unittest import mock, TestCase
+from string import ascii_letters, digits
+from unittest import mock
+
+import pytest
 
 from briar.api.models.contacts import Contacts
 
 
-class TestContacts(TestCase):
+@requests_mock.Mocker(kw='requests_mock')
+def test_get_empty(api, request_headers, requests_mock):
+    contacts = Contacts(api)
+    response = []
+
+    requests_mock.register_uri("GET", "http://localhost:7000/v1/contacts",
+                               request_headers=request_headers,
+                               text=json.dumps(response))
+    assert contacts.get() == response
 
-    # TODO: randomly generate token
-    AUTH_TOKEN = "xxhQhFNdq5R2YcipNcT3uYoMyOT2PxBl3tpWiO5Qy65w="
 
-    @requests_mock.Mocker()
-    def test_get_empty(self, requests_mock):
-        api = TestContacts._get_mocked_api()
-        request_headers = TestContacts._get_mocked_request_headers()
+@pytest.fixture
+def api(auth_token):
+    api = mock.Mock()
+    api.auth_token = auth_token
+    return api
 
-        contacts = Contacts(api)
-        response = list()
 
-        requests_mock.register_uri("GET", "http://localhost:7000/v1/contacts",
-                                   request_headers=request_headers,
-                                   text=json.dumps(response))
-        assert contacts.get() == response
+@pytest.fixture
+def request_headers(auth_token):
+    request_headers = {
+        "Authorization": 'Bearer %s' % auth_token
+        }
+    return request_headers
 
-    # TODO: Use pytest fixtures
-    def _get_mocked_api():
-        api = mock.Mock()
-        api.auth_token = TestContacts.AUTH_TOKEN
-        return api
 
-    # TODO: Use pytest fixtures
-    def _get_mocked_request_headers():
-        request_headers = {}
-        authorization_header = 'Bearer %s' % TestContacts.AUTH_TOKEN
-        request_headers["Authorization"] = authorization_header
-        return request_headers
+@pytest.fixture
+def auth_token():
+    return ''.join(choices(ascii_letters + digits, k=33))
diff --git a/tests/briar/api/test_constants.py b/tests/briar/api/test_constants.py
index 9ddf5ff94d815761ddaaa5f66a1e23592226c933..45376bcf68ec7fd9ad2d7ee6e52a85026c93c54c 100644
--- a/tests/briar/api/test_constants.py
+++ b/tests/briar/api/test_constants.py
@@ -4,28 +4,29 @@
 
 from os.path import join
 from pathlib import Path
-from unittest import TestCase
+
+import pytest
 
 from briar.api.constants import BASE_HTTP_URL, BRIAR_AUTH_TOKEN
 from briar.api.constants import BRIAR_DB, WEBSOCKET_URL
 
 
-class TestConstants(TestCase):
+def test_base_http_url():
+    assert BASE_HTTP_URL == "http://localhost:7000/v1/"
+
+
+def test_briar_auth_token(briar_dir):
+    assert BRIAR_AUTH_TOKEN == join(briar_dir, "auth_token")
+
 
-    def test_base_http_url(self):
-        assert BASE_HTTP_URL == "http://localhost:7000/v1/"
+def test_briar_db(briar_dir):
+    assert BRIAR_DB == join(briar_dir, "db", "db.mv.db")
 
-    def test_briar_auth_token(self):
-        briar_dir = TestConstants._get_briar_dir()
-        assert BRIAR_AUTH_TOKEN == join(briar_dir, "auth_token")
 
-    def test_briar_db(self):
-        briar_dir = TestConstants._get_briar_dir()
-        assert BRIAR_DB == join(briar_dir, "db", "db.mv.db")
+def test_websocket_url():
+    assert WEBSOCKET_URL == "ws://localhost:7000/v1/ws"
 
-    def test_websocket_url(self):
-        assert WEBSOCKET_URL == "ws://localhost:7000/v1/ws"
 
-    # TODO: Use pytest fixtures
-    def _get_briar_dir():
-        return join(str(Path.home()), ".briar")
+@pytest.fixture
+def briar_dir():
+    return join(str(Path.home()), ".briar")
diff --git a/tests/briar/gtk/test_define.py b/tests/briar/gtk/test_define.py
index 24ecb68d6690a31d5dd7b580f7d06173373c02a5..9be75b70e591b1991b802cac882d2b585c587143 100644
--- a/tests/briar/gtk/test_define.py
+++ b/tests/briar/gtk/test_define.py
@@ -2,14 +2,10 @@
 # SPDX-License-Identifier: AGPL-3.0-only
 # License-Filename: LICENSE.md
 
-from unittest import TestCase
-
 from gi.repository import Gio
 
 from briar.gtk.define import App
 
 
-class TestDefine(TestCase):
-
-    def test_app(self):
-        assert App == Gio.Application.get_default
+def test_app():
+    assert App == Gio.Application.get_default