diff --git a/app.py b/app.py
index 468d8e1..eece2b3 100644
--- a/app.py
+++ b/app.py
@@ -101,9 +101,10 @@ def rebuild_catalog():
     script = MOVIES_DIR.parent / "build_catalog.sh"
     if not script.exists():
         raise HTTPException(500, "build_catalog.sh not found at %s" % script)
+    env = dict(os.environ, MOVIES_DIR=str(MOVIES_DIR))
     try:
         subprocess.run(["bash", str(script)], check=True,
-                       capture_output=True, text=True, timeout=120)
+                       capture_output=True, text=True, timeout=120, env=env)
     except subprocess.CalledProcessError as e:
         raise HTTPException(500, "build failed: " + (e.stderr or e.stdout or str(e)))
     cat = load_catalog()