diff --git a/tools/flake8wrap.sh b/tools/flake8wrap.sh
new file mode 100755
index 000000000..ab3269df7
--- /dev/null
+++ b/tools/flake8wrap.sh
@@ -0,0 +1,20 @@
+#!/bin/sh
+#
+# A simple wrapper around flake8 which makes it possible
+# to ask it to only verify files changed in the current
+# git HEAD patch.
+#
+# Intended to be invoked via tox:
+#
+#   tox -epep8 -- -HEAD
+#
+
+if test "x$1" = "x-HEAD" ; then
+    shift
+    files=$(git diff --name-only HEAD~1 | tr '\n' ' ')
+    echo "Running flake8 on ${files}"
+    diff -u --from-file /dev/null ${files} | flake8 --diff "$@"
+else
+    echo "Running flake8 on all files"
+    exec flake8 "$@"
+fi
diff --git a/tox.ini b/tox.ini
index adda316ae..dee68ebfb 100644
--- a/tox.ini
+++ b/tox.ini
@@ -27,7 +27,7 @@ downloadcache = ~/cache/pip
 
 [testenv:pep8]
 commands =
-  flake8 {posargs}
+  bash tools/flake8wrap.sh {posargs}
 
 [testenv:py34]
 setenv = {[testenv]setenv}