diff --git a/dev-requirements.txt b/dev-requirements.txt
index bd84bd4..d595d4a 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -1,9 +1,10 @@
 git+https://github.com/jupyterhub/the-littlest-jupyterhub@1.0.0
-git+https://github.com/plasmabio/tljh-repo2docker
-jupyterhub~=1.5
+git+https://github.com/jtpio/tljh-repo2docker@jupyterhub-4
+jupyterhub>=4,<5
 notebook
 pytest
 pytest-aiohttp
 pytest-asyncio
 pytest-cov
+pytest-jupyterhub
 requests-mock
diff --git a/pytest.ini b/pytest.ini
index 0ee949b..cc244a3 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1,2 +1,3 @@
 [pytest]
 python_files = test_*.py
+asyncio_mode = auto
diff --git a/tljh-plasma/tljh_plasma/tests/conftest.py b/tljh-plasma/tljh_plasma/tests/conftest.py
index 2f21b20..1c80c27 100644
--- a/tljh-plasma/tljh_plasma/tests/conftest.py
+++ b/tljh-plasma/tljh_plasma/tests/conftest.py
@@ -1,17 +1,10 @@
 import asyncio
+import os
 import sys
 
 import pytest
 
-from jupyterhub.tests.conftest import (
-    io_loop,
-    event_loop,
-    db,
-    pytest_collection_modifyitems,
-)
-from jupyterhub.tests.mocking import MockHub, MockPAMAuthenticator
 from tljh_repo2docker.tests.conftest import (
-    DummyConfig,
     minimal_repo,
     image_name,
     generated_image_name,
@@ -20,40 +13,16 @@
 from tljh_repo2docker.tests.utils import add_environment
 from tljh_repo2docker import tljh_custom_jupyterhub_config as tljh_repo2docker_config
 from tljh_plasma import tljh_custom_jupyterhub_config as tljh_plasma_config
+from traitlets.config import Config
 
 
-@pytest.fixture(scope="module")
-def app(request, io_loop):
-    """
-    Adapted from:
-    https://github.com/jupyterhub/jupyterhub/blob/8a3790b01ff944c453ffcc0486149e2a58ffabea/jupyterhub/tests/conftest.py#L74
-    """
-
-    # create a JupyterHub mock instance
-    mocked_app = MockHub.instance()
-    c = DummyConfig()
-    c.JupyterHub = mocked_app
-
-    # apply the config from the plugins
-    tljh_repo2docker_config(c)
-    tljh_plasma_config(c)
-
-    # switch back to the MockPAMAuthenticator for the tests
-    c.JupyterHub.authenticator_class = MockPAMAuthenticator
-
-    async def make_app():
-        await mocked_app.initialize([])
-        await mocked_app.start()
+@pytest.fixture
+async def app(hub_app):
+    config = Config()
+    config.authenticator_class = 'jupyterhub.tests.mocking.MockPAMAuthenticator'
 
-    def fin():
-        # disconnect logging during cleanup because pytest closes captured FDs prematurely
-        mocked_app.log.handlers = []
-        MockHub.clear_instance()
-        try:
-            mocked_app.stop()
-        except Exception as e:
-            print("Error stopping Hub: %s" % e, file=sys.stderr)
+    tljh_repo2docker_config(config)
+    tljh_plasma_config(config)
 
-    request.addfinalizer(fin)
-    io_loop.run_sync(make_app)
-    return mocked_app
+    app = await hub_app(config=config)
+    return app
\ No newline at end of file