diff --git a/scripts/dev.sh b/scripts/dev.sh
index 88cab5f..0ef7eca 100755
--- a/scripts/dev.sh
+++ b/scripts/dev.sh
@@ -51,10 +51,14 @@ case "${1:-}" in
     "${COMPOSE[@]}" ps
     ;;
   down)
-    "${COMPOSE[@]}" down
+    # --remove-orphans cleans up containers from manual `docker compose
+    # -f docker-compose.yml ...` invocations (e.g., the prod-mode gunicorn
+    # smoke test) that landed in the same compose project but aren't
+    # services in the override.
+    "${COMPOSE[@]}" down --remove-orphans
     ;;
   reset-db)
-    "${COMPOSE[@]}" down --volumes
+    "${COMPOSE[@]}" down --volumes --remove-orphans
     "${COMPOSE[@]}" up -d --build mysql api-server web-view
     ;;
   logs)