diff --git a/shared/datastore/src/put.py b/shared/datastore/src/put.py
index fdd64c3..3e6c99e 100644
--- a/shared/datastore/src/put.py
+++ b/shared/datastore/src/put.py
@@ -1,10 +1,6 @@
 """Definition of put function."""
 
-from __future__ import annotations
-
 import logging
-import os
-from hashlib import md5
 from io import BytesIO
 
 from minio import Minio
@@ -13,14 +9,16 @@ from minio import Minio
 def put(
     client: Minio,
     buffer: BytesIO,
-) -> str:
+    bucket_name: str,
+    object_name: str,
+) -> None:
     """Put buffer in bucket in MinIO and return MD5 checksum as object name."""
     assert isinstance(client, Minio)
     assert isinstance(buffer, BytesIO)
-    bucket_name = os.getenv('MINIO_BUCKET_NAME', default='')
+    assert isinstance(bucket_name, str)
     assert len(bucket_name) > 0
-    # get md5 of image
-    checksum = md5(buffer.getbuffer()).hexdigest()
+    assert isinstance(object_name, str)
+    assert len(object_name) > 0
     # prepare for saving
     num_bytes = buffer.tell()
     buffer.seek(0)
@@ -28,12 +26,11 @@ def put(
     try:
         client.put_object(
             bucket_name=bucket_name,
-            object_name=checksum,
+            object_name=object_name,
             length=num_bytes,
             data=buffer,
         )
     except Exception as exc:
         logging.error('failed saving data to MinIO')
         raise exc
-    logging.debug('saved data to %s', checksum)
-    return checksum
+    logging.debug('saved data to %s', object_name)