diff --git a/bugbear.py b/bugbear.py
index 96052aa..2d012ec 100644
--- a/bugbear.py
+++ b/bugbear.py
@@ -46,7 +46,7 @@
 Context = namedtuple("Context", ["node", "stack"])
 
 
-@attr.s(hash=False)
+@attr.s(unsafe_hash=False)
 class BugBearChecker:
     name = "flake8-bugbear"
     version = __version__