diff --git a/server.py b/server.py
index 8657d2c..038f52d 100644
--- a/server.py
+++ b/server.py
@@ -78,12 +78,12 @@ async def create_upload_file(file: UploadFile | None, package: Annotated[str, Fo
             os.makedirs(dir_last)
         if not os.path.exists(dir_stable):
             os.makedirs(dir_stable)
-        with open(f"{dir_file}/{filename}", 'a') as f:
+        with open(f"{dir_file}/{filename}", 'wb+') as f:
             f.write(contents)
-        with open(f"{dir_last}/{filename}", 'a') as f:
+        with open(f"{dir_last}/{filename}", 'wb+') as f:
             f.write(contents)
         if stable:
-            with open(f"{dir_stable}/{filename}", 'a') as f:
+            with open(f"{dir_stable}/{filename}", 'wb+') as f:
                 f.write(contents)
     except Exception as err:
         return {"message": "There was an error uploading the file, error {err}".format(err=err)}