diff --git a/Makefile b/Makefile
index d32cf3f..a673e05 100644
--- a/Makefile
+++ b/Makefile
@@ -31,7 +31,12 @@ install-servers:
 	done
 
 install-test: install-servers
-	pip install pytest pytest-xprocess pytest-localserver hypothesis pytest-subtesthack
+	pip install \
+		pytest==2.8.5 \
+		pytest-xprocess \
+		pytest-localserver \
+		hypothesis \
+		pytest-subtesthack
 	[ $(TRAVIS) != "true" ] || pip install coverage codecov
 
 test: