diff --git a/swh/scheduler/tests/conftest.py b/swh/scheduler/tests/conftest.py
--- a/swh/scheduler/tests/conftest.py
+++ b/swh/scheduler/tests/conftest.py
@@ -13,7 +13,6 @@
 from swh.core.utils import numfile_sortkey as sortkey
 from swh.scheduler import get_scheduler
 from swh.scheduler.tests import SQL_DIR
-from swh.scheduler.tests.tasks import register_test_tasks
 
 
 # make sure we are not fooled by CELERY_ config environment vars
@@ -62,15 +61,14 @@
         }
 
 
-# override the celery_session_app fixture to monkeypatch the 'main'
+# use the celery_session_app fixture to monkeypatch the 'main'
 # swh.scheduler.celery_backend.config.app Celery application
-# with the test application (and also register test tasks)
+# with the test application
 @pytest.fixture(scope='session')
 def swh_app(celery_session_app):
-    from swh.scheduler.celery_backend.config import app
-    register_test_tasks(celery_session_app)
-    app = celery_session_app  # noqa
-    yield app
+    from swh.scheduler.celery_backend import config
+    config.app = celery_session_app
+    yield celery_session_app
 
 
 @pytest.fixture
diff --git a/swh/scheduler/tests/tasks.py b/swh/scheduler/tests/tasks.py
--- a/swh/scheduler/tests/tasks.py
+++ b/swh/scheduler/tests/tasks.py
@@ -5,39 +5,34 @@
 
 from celery import group
 
+from swh.scheduler.celery_backend.config import app
 
-def register_test_tasks(app):
-    """Register test tasks for the specific app passed as parameter.
-
-    In the test context, app is the swh_app and not the runtime one.
-
-    Args:
-        app: Celery app. Expects the tests application
-            (swh.scheduler.tests.conftest.swh_app)
-
-    """
-    @app.task(name='swh.scheduler.tests.tasks.ping', bind=True)
-    def ping(self, **kw):
-        # check this is a SWHTask
-        assert hasattr(self, 'log')
-        assert not hasattr(self, 'run_task')
-        assert 'SWHTask' in [x.__name__ for x in self.__class__.__mro__]
-        self.log.debug(self.name)
-        if kw:
-            return 'OK (kw=%s)' % kw
-        return 'OK'
-
-    @app.task(name='swh.scheduler.tests.tasks.multiping', bind=True)
-    def multiping(self, n=10):
-        promise = group(ping.s(i=i) for i in range(n))()
-        self.log.debug('%s OK (spawned %s subtasks)' % (self.name, n))
-        promise.save()
-        return promise.id
-
-    @app.task(name='swh.scheduler.tests.tasks.error')
-    def not_implemented():
-        raise NotImplementedError('Nope')
-
-    @app.task(name='swh.scheduler.tests.tasks.add')
-    def add(x, y):
-        return x + y
+
+@app.task(name='swh.scheduler.tests.tasks.ping', bind=True)
+def ping(self, **kw):
+    # check this is a SWHTask
+    assert hasattr(self, 'log')
+    assert not hasattr(self, 'run_task')
+    assert 'SWHTask' in [x.__name__ for x in self.__class__.__mro__]
+    self.log.debug(self.name)
+    if kw:
+        return 'OK (kw=%s)' % kw
+    return 'OK'
+
+
+@app.task(name='swh.scheduler.tests.tasks.multiping', bind=True)
+def multiping(self, n=10):
+    promise = group(ping.s(i=i) for i in range(n))()
+    self.log.debug('%s OK (spawned %s subtasks)' % (self.name, n))
+    promise.save()
+    return promise.id
+
+
+@app.task(name='swh.scheduler.tests.tasks.error')
+def not_implemented():
+    raise NotImplementedError('Nope')
+
+
+@app.task(name='swh.scheduler.tests.tasks.add')
+def add(x, y):
+    return x + y