diff --git a/test-requirements.txt b/test-requirements.txt
index d4986482..71c1c3c4 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1,4 +1,4 @@
+hacking!=0.13.0,<0.14,>=0.12.0
 bashate >= 0.2
 PyYAML >= 3.1.0
 yamllint >= 0.5.2
-flake8 < 3.6.0
diff --git a/tox.ini b/tox.ini
index bb0bba19..08b17a61 100644
--- a/tox.ini
+++ b/tox.ini
@@ -41,12 +41,30 @@ commands =
   flake8
 
 [flake8]
+# H102  Apache 2.0 license header not found
+# H104  File contains nothing but comments
+# H105  Don't use author tags
+# H233  Python 3.x incompatible use of print operator
+# H236  Python 3.x incompatible __metaclass__
+# H238  old style class declaration, use new style
+# H301  one import per line
+# H306  imports not in alphabetical order
+# H401  docstring should not start with a space
+# H403  multi line docstrings should end on a new line
+# H404  multi line docstring should start without a leading new line
+# H405  multi line docstring summary not separated with an empty line
+# H702  Argument to ... must be a string
+# H903  Windows style line endings not allowed in code
 # E123, E125 skipped as they are invalid PEP-8.
 # E501 skipped because some of the code files include templates
 #      that end up quite wide
 show-source = True
-ignore = E123,E125,E501,H405
+ignore = H102,H104,H105,H233,H236,H238,H301,H306,H401,H403,H404,H405,H702,H903,E123,E125,E501
 exclude = .venv,.git,.tox,dist,doc,*lib/python*,*egg,build,release-tag-*
+# TODO: H106 Don’t put vim configuration in source files (off by default).
+# H203 Use assertIs(Not)None to check for None (off by default).
+# TODO: H904 Delay string interpolations at logging calls (off by default).
+enable-extensions = H203
 
 [testenv:venv]
 basepython = python3