diff --git a/scripts/run_tests.sh b/scripts/run_tests.sh
index f1d1c58a2a..47994032ea 100755
--- a/scripts/run_tests.sh
+++ b/scripts/run_tests.sh
@@ -37,5 +37,5 @@ npm test
 display_result $? 3 "Front end code style check"
 
 ## Code coverage
-py.test -n4 --maxfail=10 --cov=app --cov-report=term-missing tests/ --junitxml=test_results.xml --strict -p no:warnings
+py.test -n auto --maxfail=10 --cov=app --cov-report=term-missing tests/ --junitxml=test_results.xml --strict -p no:warnings
 display_result $? 4 "Code coverage"
diff --git a/tests/conftest.py b/tests/conftest.py
index dc89436b77..30f84054aa 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -36,7 +36,7 @@ class ElementNotFound(Exception):
     pass
 
 
-@pytest.fixture
+@pytest.fixture(scope='session')
 def app_(request):
     app = Flask('app')
     create_app(app)
@@ -47,8 +47,6 @@ def app_(request):
     app.test_client_class = TestClient
     yield app
 
-    ctx.pop()
-
 
 @pytest.fixture(scope='function')
 def service_one(api_user_active):