diff --git a/conftest.py b/conftest.py
new file mode 100644
index 0000000..38825f5
--- /dev/null
+++ b/conftest.py
@@ -0,0 +1,20 @@
+import sys
+def pytest_addoption(parser):
+    parser.addoption("--stdin", action="append", default=[],
+        help="json with the stdin to pass to test functions")
+
+def pytest_generate_tests(metafunc):
+    if 'stdin' in metafunc.fixturenames:
+        metafunc.parametrize("stdin",metafunc.config.getoption('stdin'))
+
+    if 'app' in metafunc.fixturenames:
+        try:
+          sys.path.append('./.breathecode/dist')
+          import cached_app
+          metafunc.parametrize("app",[cached_app.execute_app])
+        except SyntaxError:
+          metafunc.parametrize("app",[lambda : None])
+        except ImportError:
+          metafunc.parametrize("app",[cached_app])
+        except AttributeError:
+          metafunc.parametrize("app",[cached_app])