diff --git a/public/index.html b/public/index.html
index 3468742..513c1d1 100644
--- a/public/index.html
+++ b/public/index.html
@@ -1090,71 +1090,48 @@ async function startUpload() {
 }
 
 // ============================================================
-// PARALLEL CHUNK UPLOAD (Option 4 — HTTP parallelism, Aspera-class speed)
-// Slices each file into 32 MB chunks, uploads 6 concurrently via POST,
-// server proxies to S3 multipart. Same approach as MASV — no UDP needed.
+// SIMPLE UPLOAD — uses /api/upload with @aws-sdk/lib-storage on server
+// Compatible with RustFS / MinIO / generic S3 endpoints.
+// XMLHttpRequest used for upload progress tracking.
 // ============================================================
-const CHUNK_SIZE    = 32 * 1024 * 1024; // 32 MB per part
-const CHUNK_WORKERS = 6;                // concurrent chunk POSTs per file
 
-async function uploadFileChunked(item, idx) {
-  const file       = item.file;
-  const totalParts = Math.ceil(file.size / CHUNK_SIZE);
-  const mime       = file.type || 'application/octet-stream';
+async function uploadFileDirect(item, idx) {
+  return new Promise((resolve, reject) => {
+    const fd = new FormData();
+    fd.append('prefix', selectedPrefix);
+    fd.append('files', item.file, item.name);
 
-  // 1. Initiate S3 multipart upload
-  const init = await api('POST','/api/upload/initiate',{
-    filename: item.name, prefix: selectedPrefix,
-    contentType: mime, totalParts,
+    const xhr = new XMLHttpRequest();
+    const pb = document.getElementById(`progbar-${idx}`);
+
+    xhr.upload.addEventListener('progress', (e) => {
+      if (e.lengthComputable) {
+        const pct = Math.round(e.loaded / e.total * 100);
+        if (pb) pb.style.width = pct + '%';
+        setFileStatus(idx, 'uploading', pct + '%');
+      }
+    });
+
+    xhr.addEventListener('load', () => {
+      try {
+        const data = JSON.parse(xhr.responseText);
+        if (xhr.status >= 200 && xhr.status < 300 && data.success) {
+          resolve(data);
+        } else {
+          reject(new Error(data.error || `Server returned ${xhr.status}`));
+        }
+      } catch (e) {
+        reject(new Error(`Bad response: ${xhr.status}`));
+      }
+    });
+
+    xhr.addEventListener('error', () => reject(new Error('Network error')));
+    xhr.addEventListener('abort', () => reject(new Error('Upload aborted')));
+
+    xhr.open('POST', '/api/upload');
+    xhr.setRequestHeader('x-auth-token', authToken);
+    xhr.send(fd);
   });
-  if (!init.success) throw new Error(init.error || 'Failed to initiate upload');
-  const { uploadId } = init;
-
-  const pb  = document.getElementById(`progbar-${idx}`);
-  let done  = 0;
-
-  // 2. Upload all parts with bounded concurrency
-  const queue = Array.from({length: totalParts}, (_,i) => i+1); // 1-indexed
-
-  async function worker() {
-    while (queue.length) {
-      const partNumber = queue.shift();
-      if (partNumber === undefined) break;
-      const start = (partNumber - 1) * CHUNK_SIZE;
-      const blob  = file.slice(start, Math.min(start + CHUNK_SIZE, file.size));
-      const fd    = new FormData();
-      fd.append('uploadId',    uploadId);
-      fd.append('partNumber',  String(partNumber));
-      fd.append('chunk',       blob, item.name);
-      const resp = await fetch('/api/upload/chunk', {
-        method: 'POST',
-        headers: { 'x-auth-token': authToken },
-        body: fd,
-      });
-      const data = await resp.json();
-      if (!data.success) throw new Error(`Part ${partNumber} failed: ${data.error}`);
-      done++;
-      const pct = Math.round(done / totalParts * 100);
-      if (pb) pb.style.width = pct + '%';
-      setFileStatus(idx, 'uploading', pct + '%');
-    }
-  }
-
-  try {
-    await Promise.all(Array.from({length: Math.min(CHUNK_WORKERS, totalParts)}, worker));
-  } catch (err) {
-    // Abort orphaned multipart upload on any chunk failure
-    fetch('/api/upload/abort', {
-      method: 'POST',
-      headers: { 'Content-Type': 'application/json', 'x-auth-token': authToken },
-      body: JSON.stringify({ uploadId }),
-    }).catch(() => {});
-    throw err;
-  }
-
-  // 3. Complete the multipart upload
-  const complete = await api('POST','/api/upload/complete',{ uploadId });
-  if (!complete.success) throw new Error(complete.error || 'Failed to complete upload');
 }
 
 async function uploadHTTP(files) {
@@ -1170,7 +1147,7 @@ async function uploadHTTP(files) {
       setFileStatus(idx,'uploading','Uploading…');
       document.getElementById(`prog-${idx}`).style.display='block';
       try {
-        await uploadFileChunked(item, idx);
+        await uploadFileDirect(item, idx);
         document.getElementById(`progbar-${idx}`).style.width='100%';
         setFileStatus(idx,'done','✓ Done'); item.status='done';
         showToast(`Uploaded: ${item.name}`,'success');