diff --git a/setup.py b/setup.py
index 3fe0805..55e866d 100644
--- a/setup.py
+++ b/setup.py
@@ -58,6 +58,6 @@
             "protobuf>=3.9",
         ],
         "backends": ["redis>=3.0", "pylibmc"],
-        "serializers": ["msgpack>=0.6,<1.0", "protobuf>=3.9"],
+        "serializers": ["msgpack>=0.6,<2.0", "protobuf>=3.9"],
     },
 )