diff --git a/CTFd/config.py b/CTFd/config.py
index 7e160f90c..a751ab938 100644
--- a/CTFd/config.py
+++ b/CTFd/config.py
@@ -1,6 +1,7 @@
 import configparser
 import os
 from distutils.util import strtobool
+from typing import Union
 
 
 class EnvInterpolation(configparser.BasicInterpolation):
@@ -174,7 +175,7 @@ class ServerConfig(object):
         AWS_S3_ENDPOINT_URL: str = empty_str_cast(config_ini["uploads"]["AWS_S3_ENDPOINT_URL"])
 
     # === OPTIONAL ===
-    REVERSE_PROXY: bool = process_boolean_str(empty_str_cast(config_ini["optional"]["REVERSE_PROXY"], default=False))
+    REVERSE_PROXY: Union[str, bool] = empty_str_cast(config_ini["optional"]["REVERSE_PROXY"], default=False)
 
     TEMPLATES_AUTO_RELOAD: bool = process_boolean_str(empty_str_cast(config_ini["optional"]["TEMPLATES_AUTO_RELOAD"], default=True))