diff --git a/.env.sample b/.env.sample
index 117ce06..c4c21bb 100644
--- a/.env.sample
+++ b/.env.sample
@@ -5,6 +5,8 @@ DOMAIN=discourse.example.com
 #EXTRA_DOMAINS=', `www.discourse.example.com`'
 LETS_ENCRYPT_ENV=production
 
+COMPOSE_FILE=compose.yml
+
 # Admin / developer accounts (comma-separated); these become admins on signup
 DISCOURSE_DEVELOPER_EMAILS=admin@example.com
 
@@ -18,6 +20,7 @@ DISCOURSE_DEVELOPER_EMAILS=admin@example.com
 #DISCOURSE_NOTIFICATION_EMAIL=
 
 # SMTP password as a secret
+#COMPOSE_FILE=$COMPOSE_FILE:compose.smtpauth.yml
 #SECRET_SMTP_PASSWORD_VERSION=v1
 
 SECRET_DB_PASSWORD_VERSION=v1