diff --git a/tools/fast8.sh b/tools/fast8.sh
new file mode 100755
index 00000000000..489fc6b3ad8
--- /dev/null
+++ b/tools/fast8.sh
@@ -0,0 +1,5 @@
+#!/bin/bash
+
+cd $(dirname "$0")/..
+CHANGED=$(git diff --name-only HEAD~2 | tr '\n' ' ')
+diff -u --from-file /dev/null $CHANGED | flake8 --diff
diff --git a/tox.ini b/tox.ini
index 3fb6a1c76da..5505026221c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -120,6 +120,10 @@ commands =
   {toxinidir}/tools/config/check_uptodate.sh
   {toxinidir}/tools/check_exec.py {toxinidir}/cinder
 
+[testenv:fast8]
+commands =
+  {toxinidir}/tools/fast8.sh
+
 [testenv:pylint]
 deps = -r{toxinidir}/requirements.txt
        pylint==0.26.0