diff --git a/app/config.py b/app/config.py
index 637743f..2a3f695 100644
--- a/app/config.py
+++ b/app/config.py
@@ -5,6 +5,8 @@ import os
 class Config:
     """Base configuration for the Flask application."""
 
+    AUTH_MODE = os.getenv("AUTH_MODE", "db")  # "db" ou "oauth"
+
     # Secret key for sessions and cookies.
     SECRET_KEY = os.getenv("FLASK_SECRET_KEY", "change-this-secret")