diff --git a/requirements.txt b/requirements.txt
index 917d390..c80a827 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -31,7 +31,7 @@ rlp==1.1.0
 six==1.12.0
 toolz==0.9.0
 urllib3==1.24.1
-waitress==1.2.1
+waitress==2.1.1
 web3==4.8.3
 websockets==6.0
 Werkzeug==0.15.1