diff --git a/libs/api/room/upload.rs b/libs/api/room/upload.rs
index f1dfb84..30e8765 100644
--- a/libs/api/room/upload.rs
+++ b/libs/api/room/upload.rs
@@ -125,7 +125,7 @@ pub async fn upload(
     let key = format!("rooms/{}/{}", room_id, unique_name);
     let file_size = file_data.len() as i64;
 
-    let url = storage
+    let _url = storage
         .upload(&key, file_data)
         .await
         .map_err(|e| {
@@ -139,7 +139,7 @@ pub async fn upload(
     let attachment: room_attachment::ActiveModel = room_attachment::ActiveModel {
         id: Set(attachment_id),
         room: Set(room_id),
-        message: Set(None),
+        message: Set(Uuid::nil()),
         uploader: Set(user_id),
         file_name: Set(file_name.clone()),
         file_size: Set(file_size),
@@ -206,11 +206,11 @@ pub async fn get_attachment(
         .one(&service.db)
         .await
         .map_err(|e| crate::error::ApiError(service::error::AppError::InternalServerError(e.to_string())))?
-        .ok_or_else(|| crate::error::ApiError(service::error::AppError::NotFound))?;
+        .ok_or_else(|| crate::error::ApiError(service::error::AppError::NotFound("attachment not found".into())))?;
 
     // Ensure the attachment belongs to the requested room
     if attachment.room != room_id {
-        return Err(crate::error::ApiError(service::error::AppError::NotFound));
+        return Err(crate::error::ApiError(service::error::AppError::NotFound("attachment not found".into())));
     }
 
     let storage = service
@@ -223,8 +223,8 @@ pub async fn get_attachment(
         .await
         .map_err(|e| crate::error::ApiError(service::error::AppError::InternalServerError(e.to_string())))?;
 
-    HttpResponse::Ok()
-        .content_type(content_type)
+    Ok(HttpResponse::Ok()
+        .content_type(content_type.clone())
         .insert_header((
             CONTENT_TYPE,
             content_type,
@@ -233,5 +233,5 @@ pub async fn get_attachment(
             CONTENT_DISPOSITION,
             format!("inline; filename=\"{}\"", attachment.file_name),
         ))
-        .body(data)
+        .body(data))
 }
diff --git a/libs/service/project_tools/arxiv.rs b/libs/service/project_tools/arxiv.rs
index f12b04c..69f52a9 100644
--- a/libs/service/project_tools/arxiv.rs
+++ b/libs/service/project_tools/arxiv.rs
@@ -35,6 +35,7 @@ struct ArxivAuthor {
 }
 
 #[derive(Debug, Deserialize)]
+#[allow(dead_code)]
 struct ArxivLink {
     #[serde(rename = "type", default)]
     link_type: String,
diff --git a/libs/service/project_tools/boards.rs b/libs/service/project_tools/boards.rs
index dbd9dc9..c653674 100644
--- a/libs/service/project_tools/boards.rs
+++ b/libs/service/project_tools/boards.rs
@@ -41,6 +41,7 @@ async fn require_admin(
     }
 }
 
+#[allow(dead_code)]
 fn serde_user(u: &UserModel) -> serde_json::Value {
     serde_json::json!({
         "id": u.uid.to_string(),