diff --git a/backend/src/db.js b/backend/src/db.js
index 306a4be..7f2fa21 100644
--- a/backend/src/db.js
+++ b/backend/src/db.js
@@ -60,6 +60,7 @@ db.exec(`
     folder_id    INTEGER NOT NULL REFERENCES folders(id) ON DELETE CASCADE,
     shared_by    INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
     shared_with  INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+    created_at   DATETIME DEFAULT CURRENT_TIMESTAMP,
     UNIQUE(folder_id, shared_with)
   );
 
@@ -160,6 +161,10 @@ if (!ordCols.includes('bezahlt_am')) db.exec("ALTER TABLE orders ADD COLUMN beza
 const fileCols = db.prepare("PRAGMA table_info(files)").all().map(r => r.name);
 if (!fileCols.includes('folder_id')) db.exec("ALTER TABLE files ADD COLUMN folder_id INTEGER REFERENCES folders(id) ON DELETE SET NULL");
 
+// folder_shares migrations
+const fsCols = db.prepare("PRAGMA table_info(folder_shares)").all().map(r => r.name);
+if (!fsCols.includes('created_at')) db.exec("ALTER TABLE folder_shares ADD COLUMN created_at DATETIME DEFAULT CURRENT_TIMESTAMP");
+
 const oiCols = db.prepare("PRAGMA table_info(order_items)").all().map(r => r.name);
 if (!oiCols.includes('stunden')) db.exec("ALTER TABLE order_items ADD COLUMN stunden REAL NOT NULL DEFAULT 0");
 if (!oiCols.includes('custom_price'))    db.exec("ALTER TABLE order_items ADD COLUMN custom_price REAL");