diff --git a/swh/indexer/mimetype.py b/swh/indexer/mimetype.py
index 16890bf..dec2689 100644
--- a/swh/indexer/mimetype.py
+++ b/swh/indexer/mimetype.py
@@ -1,151 +1,153 @@
 # Copyright (C) 2016-2017  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import click
 
 from subprocess import Popen, PIPE
 from swh.scheduler import utils
 
 from .indexer import BaseIndexer
 
 
 def compute_mimetype_encoding(raw_content):
     """Determine mimetype and encoding from the raw content.
 
     Args:
         raw_content (bytes): content's raw data
 
     Returns:
         A dict with mimetype and encoding key and corresponding values.
 
     """
     with Popen(['file', '--mime', '-'], stdin=PIPE,
                stdout=PIPE, stderr=PIPE) as p:
         properties, _ = p.communicate(raw_content)
 
         if properties:
             res = properties.split(b': ')[1].strip().split(b'; ')
             mimetype = res[0]
             encoding = res[1].split(b'=')[1]
             return {
                 'mimetype': mimetype,
                 'encoding': encoding
             }
 
 
 class ContentMimetypeIndexer(BaseIndexer):
     """Indexer in charge of:
     - filtering out content already indexed
     - reading content from objstorage per the content's id (sha1)
     - computing {mimetype, encoding} from that content
     - store result in storage
 
     """
     ADDITIONAL_CONFIG = {
         # chained queue message, e.g:
         # swh.indexer.tasks.SWHOrchestratorTextContentsTask
         'destination_queue': ('str', None),
         'tools': ('dict', {
             'name': 'file',
             'version': '5.22',
-            'configuration': 'file --mime <filename>',
+            'configuration': {
+                'command_line': 'file --mime <filename>',
+            },
         }),
     }
 
     CONFIG_BASE_FILENAME = 'indexer/mimetype'
 
     def __init__(self):
         super().__init__()
         destination_queue = self.config.get('destination_queue')
         if destination_queue:
             self.task_destination = utils.get_task(destination_queue)
         else:
             self.task_destination = None
 
     def filter_contents(self, sha1s):
         """Filter out known sha1s and return only missing ones.
 
         """
         yield from self.storage.content_mimetype_missing((
             {
                 'id': sha1,
                 'indexer_configuration_id': self.tools['id'],
             } for sha1 in sha1s
         ))
 
     def index_content(self, sha1, raw_content):
         """Index sha1s' content and store result.
 
         Args:
             sha1 (bytes): content's identifier
             raw_content (bytes): raw content in bytes
 
         Returns:
             A dict, representing a content_mimetype, with keys:
               - id (bytes): content's identifier (sha1)
               - mimetype (bytes): mimetype in bytes
               - encoding (bytes): encoding in bytes
 
         """
         properties = compute_mimetype_encoding(raw_content)
         properties.update({
             'id': sha1,
             'indexer_configuration_id': self.tools['id'],
         })
 
         return properties
 
     def persist_index_computations(self, results, policy_update):
         """Persist the results in storage.
 
         Args:
             results ([dict]): list of content_mimetype, dict with the
             following keys:
               - id (bytes): content's identifier (sha1)
               - mimetype (bytes): mimetype in bytes
               - encoding (bytes): encoding in bytes
             policy_update ([str]): either 'update-dups' or 'ignore-dups' to
             respectively update duplicates or ignore them
 
         """
         self.storage.content_mimetype_add(
             results, conflict_update=(policy_update == 'update-dups'))
 
     def _filter_text(self, results):
         """Filter sha1 whose raw content is text.
 
         """
         for result in results:
             if b'binary' in result['encoding']:
                 continue
             yield result['id']
 
     def next_step(self, results):
         """When the computations is done, we'd like to send over only text
         contents to the text content orchestrator.
 
         Args:
             results ([dict]): List of content_mimetype results, dict
             with the following keys:
               - id (bytes): content's identifier (sha1)
               - mimetype (bytes): mimetype in bytes
               - encoding (bytes): encoding in bytes
 
         """
         if self.task_destination:
             self.task_destination.delay(list(self._filter_text(results)))
 
 
 @click.command()
 @click.option('--path', help="Path to execute index on")
 def main(path):
     with open(path, 'rb') as f:
         raw_content = f.read()
 
     print(compute_mimetype_encoding(raw_content))
 
 
 if __name__ == '__main__':
     main()