diff --git a/.gitreview b/.gitreview
index be7b3b49..b4a4dd62 100644
--- a/.gitreview
+++ b/.gitreview
@@ -2,3 +2,4 @@
 host=review.opendev.org
 port=29418
 project=openstack/python-magnumclient.git
+defaultbranch=stable/2026.1
diff --git a/test-requirements.txt b/test-requirements.txt
index a15caacf..b5d097f6 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -5,6 +5,7 @@ fixtures>=3.0.0 # Apache-2.0/BSD
 python-openstackclient>=3.12.0 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
 osprofiler>=1.4.0 # Apache-2.0
+requests-mock>=1.2.0 # Apache-2.0
 stestr>=2.0.0 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
diff --git a/tox.ini b/tox.ini
index 46c85ddb..1c6f4e6d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,7 +9,7 @@ setenv =
    VIRTUAL_ENV={envdir}
    PYTHONWARNINGS=default::DeprecationWarning
 deps =
-  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/2026.1}
   -r{toxinidir}/requirements.txt
   -r{toxinidir}/test-requirements.txt
 commands =
@@ -19,7 +19,7 @@ commands =
 [testenv:bandit]
 basepython = python3
 deps =
-  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/2026.1}
   -r{toxinidir}/test-requirements.txt
 commands = bandit -r magnumclient -x tests -n5 -ll