diff --git a/src/server.rs b/src/server.rs
index e3a3f84..532874e 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -860,7 +860,8 @@ async fn upload_file(
         )?;
 
         // Create file node
-        let node_id = format!("node-{}", uuid::Uuid::new_v4().to_string().replace('-', "")[0..8]);
+        let uuid_str = uuid::Uuid::new_v4().to_string().replace('-', "");
+        let node_id = format!("node-{}", uuid_str.chars().take(8).collect::<String>());
         
         conn.execute(
             "INSERT INTO file_nodes (node_id, label, file_uuid, sha256, node_type, file_size, created_at, updated_at)