diff --git a/backend/src/model.rs b/backend/src/model.rs
index 57b0163..4121fcb 100644
--- a/backend/src/model.rs
+++ b/backend/src/model.rs
@@ -1,6 +1,6 @@
 use axum::{body::Bytes, extract::multipart::MultipartError};
 use futures_util::{Stream, StreamExt};
-use opendal::{Operator, layers::LoggingLayer, services};
+use opendal::{FuturesBytesStream, Operator, layers::LoggingLayer, services};
 use serde::Serialize;
 use sqlx::{PgPool, prelude::FromRow};
 
@@ -80,22 +80,14 @@ impl FileRepository {
         Ok(record)
     }
 
-    pub async fn download_file(
-        &self,
-        file_id: i64,
-        user_id: i64,
-    ) -> Result<impl Stream<Item = std::io::Result<Bytes>> + use<>> {
+    pub async fn download_file(&self, file_id: i64, user_id: i64) -> Result<FuturesBytesStream> {
         let record = self.get_file(file_id, user_id).await?;
         let reader = self.op.reader(&record.storage_key).await?;
         let stream = reader.into_bytes_stream(0..).await?;
         Ok(stream)
     }
 
-    pub async fn thumbnail(
-        &self,
-        file_id: i64,
-        user_id: i64,
-    ) -> Result<impl Stream<Item = std::io::Result<Bytes>> + use<>> {
+    pub async fn thumbnail(&self, file_id: i64, user_id: i64) -> Result<FuturesBytesStream> {
         let record = self.get_file(file_id, user_id).await?;
         let path = format!("thumbnail/{}", &record.storage_key);
         let reader = self.op.reader(&path).await?;
@@ -109,7 +101,7 @@ impl FileRepository {
         user_id: i64,
         from: u64,
         to: u64,
-    ) -> Result<impl Stream<Item = std::io::Result<Bytes>> + use<>> {
+    ) -> Result<FuturesBytesStream> {
         let record = self.get_file(file_id, user_id).await?;
         let reader = self.op.reader(&record.storage_key).await?;
         let stream = reader.into_bytes_stream(from..to).await?;
@@ -435,7 +427,7 @@ mod tests {
             .await
             .unwrap();
 
-            assert_eq!(record.thumbnail_storage_path, None);
+        assert_eq!(record.thumbnail_storage_path, None);
 
         let path = "thumbnail/a.png-uuid";
         file_repository