diff --git a/tox.ini b/tox.ini
index f60580697..37d6fd8ad 100644
--- a/tox.ini
+++ b/tox.ini
@@ -10,7 +10,7 @@ passenv = OS_*
           REQUIREMENTS_PIP_LOCATION
 install_command = pip install {opts} {packages}
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/nats-driver}
   -r{toxinidir}/test-requirements.txt
   -r{toxinidir}/requirements.txt
 commands = stestr run --slowest {posargs}