diff --git a/tox.ini b/tox.ini
index 226078e1d..e6c26e9d3 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,7 @@ envlist = py27,pep8
 usedevelop = True
 install_command = pip install {opts} {packages}
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt?h=stable/queens}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/queens}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/test-requirements.txt
 commands=
@@ -20,6 +20,7 @@ commands =
 commands = {posargs}
 
 [testenv:pep8]
+basepython = python2.7
 commands = ./run-flake8
 
 [flake8]