diff --git a/tox.ini b/tox.ini
index 7ff2d0248a..d50be28a92 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,6 +8,8 @@ envlist =
 [testenv]
 deps =
     -rrequirements.txt
+    pytest
 commands =
     python -m compileall trezorlib/
     python trezorctl --help
+    python -m pytest --pyarg trezorlib.tests.unit_tests