pin pytest to disallow 2.8.4 which breaks tests
diff --git a/dev-requirements.txt b/dev-requirements.txt
index c409ff9..9aca5dd 100644
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -7,7 +7,7 @@
 pep8-naming
 pretend
 pyasn1_modules
-pytest
+pytest!=2.8.4
 requests
 sphinx==1.3.1
 sphinx_rtd_theme
diff --git a/setup.py b/setup.py
index 19f1e66..43fe17e 100644
--- a/setup.py
+++ b/setup.py
@@ -59,7 +59,7 @@
 
 # If you add a new dep here you probably need to add it in the tox.ini as well
 test_requirements = [
-    "pytest",
+    "pytest!=2.8.4",
     "pretend",
     "iso8601",
     "hypothesis",
diff --git a/tox.ini b/tox.ini
index 63f1e4b..cf899b7 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,7 @@
     coverage
     iso8601
     pretend
-    pytest
+    pytest!=2.8.4
     hypothesis>=1.11.4
     pyasn1_modules
     ./vectors