diff --git a/src/back/test_utils/with-prod-app.ts b/src/back/test_utils/with-prod-app.ts
index b936c5f..3722611 100644
--- a/src/back/test_utils/with-prod-app.ts
+++ b/src/back/test_utils/with-prod-app.ts
@@ -39,7 +39,7 @@ export async function withProdApp(
 	};
 	app.config.logger.level = <const>"none";
 	app.mailer = new SMTPMailer({
-		host: "127.0.0.1",
+		host: MAILCATCHER_HOST,
 		port: MAILCATCHER_SMTP_PORT,
 		user: "any",
 		password: "any",