diff --git a/requirements.txt b/requirements.txt
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 vcversioner
 click
-file-magic
+python-magic >= 0.4.13
 pyld
 xmltodict
diff --git a/swh/indexer/mimetype.py b/swh/indexer/mimetype.py
--- a/swh/indexer/mimetype.py
+++ b/swh/indexer/mimetype.py
@@ -5,10 +5,13 @@
 
 import magic
 
-from swh.model import hashutil
-
 from .indexer import ContentIndexer, ContentRangeIndexer
 
+if not hasattr(magic.Magic, 'from_buffer'):
+    raise ImportError(
+        'Expected "import magic" to import python-magic, but file_magic '
+        'was imported instead.')
+
 
 def compute_mimetype_encoding(raw_content):
     """Determine mimetype and encoding from the raw content.
@@ -21,10 +24,12 @@
         (as bytes).
 
     """
-    r = magic.detect_from_content(raw_content)
+    m = magic.Magic(mime=True, mime_encoding=True)
+    res = m.from_buffer(raw_content)
+    (mimetype, encoding) = res.split('; charset=')
     return {
-        'mimetype': r.mime_type,
-        'encoding': r.encoding,
+        'mimetype': mimetype,
+        'encoding': encoding,
     }
 
 
@@ -63,17 +68,11 @@
             - **encoding** (bytes): encoding in bytes
 
         """
-        try:
-            properties = compute_mimetype_encoding(data)
-            properties.update({
-                'id': id,
-                'indexer_configuration_id': self.tool['id'],
-                })
-        except TypeError:
-            self.log.error('Detecting mimetype error for id %s' % (
-                hashutil.hash_to_hex(id), ))
-            return None
-
+        properties = compute_mimetype_encoding(data)
+        properties.update({
+            'id': id,
+            'indexer_configuration_id': self.tool['id'],
+            })
         return properties
 
     def persist_index_computations(self, results, policy_update):