diff --git a/tox.ini b/tox.ini
index 27a7c09..54a6ee2 100644
--- a/tox.ini
+++ b/tox.ini
@@ -11,8 +11,11 @@ basepython = python3
 install_command = pip install {opts} {packages}
 deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
+allowlist_externals = bash
 commands =
-  python setup.py testr --slowest --testr-args='{posargs}'
+  bash -c "[ -d .testrepository ] || testr init"
+  testr run -- {posargs}
+  testr slowest
 
 [tox:jenkins]
 sitepackages = True
@@ -22,8 +25,10 @@ commands = flake8
 
 [testenv:cover]
 setenv = VIRTUAL_ENV={envdir}
+allowlist_externals = bash
 commands =
-  python setup.py testr --coverage
+  bash -c "[ -d .testrepository ] || testr init"
+  testr --coverage
 
 [testenv:venv]
 commands = {posargs}