diff --git a/tox.ini b/tox.ini
index fe2ced727..04cf129c5 100644
--- a/tox.ini
+++ b/tox.ini
@@ -13,6 +13,7 @@ passenv =
 setenv =
     SMOKE_TEST = true
     BAYBE_TEST_ENV = FULLTEST
+    PYTHONDONTWRITEBYTECODE = false
 commands =
     python --version
     pytest -p no:warnings --cov=baybe --durations=5 {posargs}
@@ -27,6 +28,7 @@ passenv =
 setenv =
     SMOKE_TEST = true
     BAYBE_TEST_ENV = CORETEST
+    PYTHONDONTWRITEBYTECODE = false
 commands =
     python --version
     pytest -p no:warnings --cov=baybe --durations=5 {posargs}