diff --git a/tox.ini b/tox.ini
index 3538a6b..855ab4f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -9,18 +9,18 @@ ignore_basepython_conflict = True
 basepython = python3
 usedevelop = True
 setenv =
-   VIRTUAL_ENV={envdir}
-   OS_STDOUT_CAPTURE=1
-   OS_STDERR_CAPTURE=1
-   OS_TEST_TIMEOUT=500
+  VIRTUAL_ENV={envdir}
+  OS_STDOUT_CAPTURE=1
+  OS_STDERR_CAPTURE=1
+  OS_TEST_TIMEOUT=500
 allowlist_externals = find
 deps =
-       -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
-       -r{toxinidir}/requirements.txt
-       -r{toxinidir}/test-requirements.txt
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -r{toxinidir}/requirements.txt
+  -r{toxinidir}/test-requirements.txt
 commands =
-         find . -type f -name "*.pyc" -delete
-         stestr run {posargs}
+  find . -type f -name "*.pyc" -delete
+  stestr run {posargs}
 
 [testenv:pep8]
 commands = flake8
@@ -30,17 +30,17 @@ commands = {posargs}
 
 [testenv:cover]
 setenv =
-    VIRTUAL_ENV={envdir}
-    PYTHON=coverage run --source os_testr --parallel-mode
+  VIRTUAL_ENV={envdir}
+  PYTHON=coverage run --source os_testr --parallel-mode
 commands =
-    stestr run {posargs}
-    coverage combine
-    coverage html -d cover
-    coverage xml -o cover/coverage.xml
+  stestr run {posargs}
+  coverage combine
+  coverage html -d cover
+  coverage xml -o cover/coverage.xml
 
 [testenv:docs]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-build -W --keep-going -b html -d doc/build/doctrees doc/source doc/build/html
@@ -48,17 +48,17 @@ commands =
 [testenv:pdf-docs]
 deps = {[testenv:docs]deps}
 allowlist_externals =
-   make
+  make
 commands =
-   sphinx-build -W -b latex doc/source doc/build/pdf
-   make -C doc/build/pdf
+  sphinx-build -W -b latex doc/source doc/build/pdf
+  make -C doc/build/pdf
 
 [testenv:debug]
 commands = oslo_debug_helper {posargs}
 
 [testenv:releasenotes]
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+  -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf releasenotes/build