diff --git a/tox.ini b/tox.ini
index 791b55f..f3a4def 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,15 +1,16 @@
 [tox]
-minversion = 1.6
+minversion = 1.8
 envlist = py34,py27,pep8
 skipsdist = True
 
 [testenv]
 usedevelop = True
-install_command = pip install -U {opts} {packages}
+install_command =
+                  constraints: pip install -U --force-reinstall -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
+                  pip install -U {opts} {packages}
 setenv =
    VIRTUAL_ENV={envdir}
-deps = -r{toxinidir}/requirements.txt
-       -r{toxinidir}/test-requirements.txt
+deps = -r{toxinidir}/test-requirements.txt
 commands = python setup.py testr --slowest --testr-args='{posargs}'
 
 [testenv:pep8]