diff --git a/debian/bird-exporter.service b/debian/bird-exporter.service
index dfb09a4..665c788 100644
--- a/debian/bird-exporter.service
+++ b/debian/bird-exporter.service
@@ -7,8 +7,8 @@ Wants=bird.service
 [Service]
 Type=simple
 EnvironmentFile=-/etc/default/bird-exporter
-User=${BIRD_RUN_USER}
-Group=${BIRD_RUN_GROUP}
+User=${BIRD_RUN_USER:-bird}
+Group=${BIRD_RUN_GROUP:-bird}
 ExecStart=/usr/bin/bird-exporter $BIRD_EXPORTER_ARGS
 Restart=always
 RestartSec=5