diff --git a/requirements.txt b/requirements.txt
index df1e105..97d529a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -2,6 +2,7 @@ Flask==1.1.2
 Flask-Classy==0.6.10
 Flask-SocketIO==2.6.2
 greenlet==0.4.16
+eventlet==0.26.1
 
 python-engineio==3.8.2.post1
 python-socketio==1.4.4