diff --git a/backend/main.py b/backend/main.py
index e48d11f..52a7695 100644
--- a/backend/main.py
+++ b/backend/main.py
@@ -4,7 +4,7 @@ import os
 import tempfile
 import threading
 from pathlib import Path
-from typing import Optional
+from typing import List, Optional
 
 import httpx
 import yaml
@@ -195,20 +195,34 @@ async def preview_file(stage: str, filename: str, lines: int = 120):
 
 
 @app.post("/api/upload")
-async def upload_file(file: UploadFile = File(...)):
+async def upload_files(files: List[UploadFile] = File(...)):
     _require_ssh()
-
-    suffix = Path(file.filename).suffix
-    with tempfile.NamedTemporaryFile(delete=False, suffix=suffix) as tmp:
-        tmp.write(await file.read())
-        tmp_path = tmp.name
-
-    try:
-        remote_path = f"{STAGE_DIRS['input']}/{file.filename}"
-        ssh_manager.upload_file(tmp_path, remote_path)
-        return {"uploaded": file.filename, "remote_path": remote_path}
-    finally:
-        os.unlink(tmp_path)
+    results = []
+    for file in files:
+        suffix = Path(file.filename).suffix.lower()
+        with tempfile.NamedTemporaryFile(delete=False, suffix=suffix) as tmp:
+            tmp.write(await file.read())
+            tmp_path = tmp.name
+        try:
+            if suffix == ".zip":
+                remote_tmp = f"/tmp/{file.filename}"
+                ssh_manager.upload_file(tmp_path, remote_tmp)
+                input_dir = STAGE_DIRS["input"]
+                out, err, code = ssh_manager.execute(
+                    f"unzip -o '{remote_tmp}' -d '{input_dir}' "
+                    f"&& rm '{remote_tmp}'",
+                    use_conda=False,
+                )
+                if code != 0:
+                    raise HTTPException(status_code=500, detail=f"Unzip failed for {file.filename}: {err}")
+                results.append({"file": file.filename, "action": "extracted"})
+            else:
+                remote_path = f"{STAGE_DIRS['input']}/{file.filename}"
+                ssh_manager.upload_file(tmp_path, remote_path)
+                results.append({"file": file.filename, "action": "uploaded", "remote_path": remote_path})
+        finally:
+            os.unlink(tmp_path)
+    return {"results": results}
 
 
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