diff --git a/stackrc b/stackrc
index a36f897..244acbb 100644
--- a/stackrc
+++ b/stackrc
@@ -298,6 +298,7 @@
 # Tempest test suite
 TEMPEST_REPO=${TEMPEST_REPO:-${GIT_BASE}/openstack/tempest.git}
 TEMPEST_BRANCH=${TEMPEST_BRANCH:-$BRANCHLESS_TARGET_BRANCH}
+TEMPEST_VENV_UPPER_CONSTRAINTS=${TEMPEST_VENV_UPPER_CONSTRAINTS:-master}
 
 
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