diff --git a/core/src/services/azblob/core.rs b/core/src/services/azblob/core.rs
index ffd76a4a8464..a62c12bc700c 100644
--- a/core/src/services/azblob/core.rs
+++ b/core/src/services/azblob/core.rs
@@ -438,6 +438,7 @@ impl AzblobCore {
         let req = self.insert_sse_headers(req);
 
         // Set body
+        // refer to https://learn.microsoft.com/en-us/rest/api/storageservices/put-block-list?
         let req_body = {
             let block_list = block_ids
                 .iter()
diff --git a/core/src/services/azblob/writer.rs b/core/src/services/azblob/writer.rs
index fceba0f1e5d2..137bfe665dd3 100644
--- a/core/src/services/azblob/writer.rs
+++ b/core/src/services/azblob/writer.rs
@@ -111,6 +111,8 @@ impl oio::AppendWrite for AzblobWriter {
     }
 }
 
+#[cfg_attr(not(target_arch = "wasm32"), async_trait)]
+#[cfg_attr(target_arch = "wasm32", async_trait(?Send))]
 #[async_trait]
 impl oio::BlockWrite for AzblobWriter {
     async fn write_once(&self, size: u64, body: AsyncBody) -> Result<()> {