diff --git a/tox.ini b/tox.ini
index 21696eb..c35f071 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,9 +8,8 @@
 setenv =
     VIRTUAL_ENV={envdir}
     OS_TEST_PATH=./tempest/test_discover
-    BRANCH_NAME=master
-    CLIENT_NAME=tempest
 deps =
+    -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
     -r{toxinidir}/requirements.txt
 
 [testenv]
@@ -18,14 +17,12 @@
     VIRTUAL_ENV={envdir}
     OS_LOG_CAPTURE=1
     PYTHONWARNINGS=default::DeprecationWarning
-    BRANCH_NAME=master
-    CLIENT_NAME=tempest
 passenv = OS_STDOUT_CAPTURE OS_STDERR_CAPTURE OS_TEST_TIMEOUT OS_TEST_LOCK_PATH TEMPEST_CONFIG TEMPEST_CONFIG_DIR http_proxy HTTP_PROXY https_proxy HTTPS_PROXY no_proxy NO_PROXY ZUUL_CACHE_DIR REQUIREMENTS_PIP_LOCATION GENERATE_TEMPEST_PLUGIN_LIST
 usedevelop = True
-install_command =
-    {toxinidir}/tools/tox_install.sh {env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
+install_command = pip install {opts} {packages}
 whitelist_externals = *
 deps =
+    -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/test-requirements.txt
 commands =