diff --git a/requirements.txt b/requirements.txt
index 9fb7dbb..9a66b60 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -53,6 +53,8 @@ service-identity==23.1.0
 six==1.16.0
 sniffio==1.3.0
 starlette==0.27.0
+# StrEnum for python < 3.11
+StrEnum==0.4.15
 tldextract==3.6.0
 Twisted==22.10.0
 typing_extensions==4.8.0