diff --git a/tox.ini b/tox.ini
index 50572a6..2cc7023 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,7 +8,7 @@ skipsdist = True
 basepython = python3
 whitelist_externals = bash
 setenv = VIRTUAL_ENV={envdir}
-deps =  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+deps =  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
        -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands = bash -c 'if [ ! -d ./.testrepository ] ; then testr init ; fi'