diff --git a/hacking/checks/comments.py b/hacking/checks/comments.py
index e66e9cb3..96eaa8fa 100644
--- a/hacking/checks/comments.py
+++ b/hacking/checks/comments.py
@@ -162,8 +162,8 @@ under the License."""
     if stripped_apache2 in content:
         return True
     else:
-        print ("<license>!=<apache2>:\n'%s' !=\n'%s'" %
-               (content, stripped_apache2))
+        print("<license>!=<apache2>:\n'%s' !=\n'%s'" %
+              (content, stripped_apache2))
         return False
 
 
diff --git a/hacking/checks/vim_check.py b/hacking/checks/vim_check.py
index 17c501a1..a9c695a8 100644
--- a/hacking/checks/vim_check.py
+++ b/hacking/checks/vim_check.py
@@ -35,5 +35,5 @@ def no_vim_headers(physical_line, line_number, lines):
     Okay: # vim, ze nemluvis cesky
     """
     if ((line_number <= 5 or line_number > len(lines) - 5) and
-         vim_header_re.match(physical_line)):
+            vim_header_re.match(physical_line)):
         return 0, "H106: Don't put vim configuration in source files"
diff --git a/requirements.txt b/requirements.txt
index c98199b0..7146fceb 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -5,7 +5,7 @@ pbr>=1.6 # Apache-2.0
 
 pep8==1.5.7 # MIT
 pyflakes==0.8.1 # MIT
-flake8<2.6.0,>2.4.1 # MIT
+flake8<2.6.0,>=2.5.4 # MIT
 mccabe==0.2.1 # MIT License
 
 six>=1.9.0 # MIT
diff --git a/tox.ini b/tox.ini
index f066825b..9a54fdaf 100644
--- a/tox.ini
+++ b/tox.ini
@@ -37,7 +37,7 @@ commands = python setup.py build_sphinx
 [flake8]
 exclude = .venv,.tox,dist,doc,*.egg,build
 show-source = true
-select = H106
+enable-extensions = H106
 
 [hacking]
 local-check = hacking.tests.test_local.check