diff --git a/requirements.txt b/requirements.txt
index 50d9bf8..1a1acf8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,7 +4,7 @@ attrs==18.2.0
 codecov==2.0.15
 funcy==1.11
 lenses==0.5.0
-hypothesis==3.66.30
+hypothesis==4.5.7
 parsimonious==0.8.1
 pytest==3.2.3
 pytest-cov==2.5.1