diff --git a/pytest.ini b/pytest.ini
index 730658a778..9f6157c9b8 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1,6 +1,6 @@
 # content of pytest.ini
 [pytest]
-addopts = --durations=30 -ra
+addopts = --durations=30 -ra --strict-markers
 testpaths = lib/spack/spack/test
 python_files = *.py
 filterwarnings =