diff --git a/htsget-http-core/src/http_core.rs b/htsget-http-core/src/http_core.rs
index e50e1468a..9838624b0 100644
--- a/htsget-http-core/src/http_core.rs
+++ b/htsget-http-core/src/http_core.rs
@@ -48,7 +48,7 @@ pub async fn get_response_for_post_request(
   let mut futures = FuturesOrdered::new();
   for query in request.get_queries(id)? {
     let owned_searcher = searcher.clone();
-    futures.push(tokio::spawn(
+    futures.push_back(tokio::spawn(
       async move { owned_searcher.search(query).await },
     ));
   }
diff --git a/htsget-search/src/htsget/bcf_search.rs b/htsget-search/src/htsget/bcf_search.rs
index 00a776c22..6a1eec411 100644
--- a/htsget-search/src/htsget/bcf_search.rs
+++ b/htsget-search/src/htsget/bcf_search.rs
@@ -86,7 +86,7 @@ where
     for (ref_seq_index, (name, _)) in header.contigs().iter().enumerate() {
       let owned_name = name.to_owned();
       let owned_reference_name = reference_name.clone();
-      futures.push(tokio::spawn(async move {
+      futures.push_back(tokio::spawn(async move {
         if owned_name == owned_reference_name {
           Some((ref_seq_index, owned_name))
         } else {
diff --git a/htsget-search/src/htsget/cram_search.rs b/htsget-search/src/htsget/cram_search.rs
index 2cc51d5f1..62959a17f 100644
--- a/htsget-search/src/htsget/cram_search.rs
+++ b/htsget-search/src/htsget/cram_search.rs
@@ -204,7 +204,7 @@ where
       let owned_next = next.clone();
       let owned_predicate = predicate.clone();
       let range = interval.clone();
-      futures.push(tokio::spawn(async move {
+      futures.push_back(tokio::spawn(async move {
         if owned_predicate(&owned_record) {
           Self::bytes_ranges_for_record(range, &owned_record, owned_next.offset())
         } else {
diff --git a/htsget-search/src/htsget/search.rs b/htsget-search/src/htsget/search.rs
index cac2c0ccd..6b8c9be10 100644
--- a/htsget-search/src/htsget/search.rs
+++ b/htsget-search/src/htsget/search.rs
@@ -296,14 +296,14 @@ where
         DataBlock::Range(range) => {
           let storage = self.get_storage();
           let id = id.clone();
-          storage_futures.push(tokio::spawn(async move {
+          storage_futures.push_back(tokio::spawn(async move {
             storage
               .range_url(format.fmt_file(&id), RangeUrlOptions::from(range))
               .await
           }));
         }
         DataBlock::Data(data, class) => {
-          storage_futures.push(tokio::spawn(async move { Ok(S::data_url(data, class)) }));
+          storage_futures.push_back(tokio::spawn(async move { Ok(S::data_url(data, class)) }));
         }
       }
     }
diff --git a/htsget-search/src/htsget/vcf_search.rs b/htsget-search/src/htsget/vcf_search.rs
index 1140eefc1..e2bc8b547 100644
--- a/htsget-search/src/htsget/vcf_search.rs
+++ b/htsget-search/src/htsget/vcf_search.rs
@@ -87,7 +87,7 @@ where
     for (index, name) in index.header().reference_sequence_names().iter().enumerate() {
       let owned_name = name.to_owned();
       let owned_reference_name = reference_name.clone();
-      futures.push(tokio::spawn(async move {
+      futures.push_back(tokio::spawn(async move {
         if owned_name == owned_reference_name {
           Some(index)
         } else {