diff --git a/swh/journal/backend.py b/swh/journal/backend.py
new file mode 100644
--- /dev/null
+++ b/swh/journal/backend.py
@@ -0,0 +1,55 @@
+# Copyright (C) 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 psycopg2
+import psycopg2.extras
+
+
+def entry_to_bytes(entry):
+    """Convert an entry coming from the database to bytes"""
+    if isinstance(entry, memoryview):
+        return entry.tobytes()
+    if isinstance(entry, list):
+        return [entry_to_bytes(value) for value in entry]
+    return entry
+
+
+class Backend:
+    """Backend for Software Heritage object identifiers batch retrieval.
+
+    The need is to retrieve all the identifiers per object type fast (stream).
+    For this, the implementation is using:
+    - server side cursor
+    - one db connection per object type
+
+    """
+    _map_type_primary_key = {
+        'origin': 'id',
+        'content': 'sha1',
+        'directory': 'id',
+        'revision': 'id',
+        'release': 'id',
+    }
+
+    def __init__(self, db_conn):
+        self.db_conn = db_conn
+
+    def fetch(self, obj_type):
+        """"""
+        primary_key = self._map_type_primary_key.get(obj_type)
+        if not primary_key:
+            raise ValueError('The object type %s is not supported. '
+                             'Only possible values are %s' % (
+                                 obj_type, self._map_type_primary_key.keys()))
+
+        query = 'select %s from %s order by %s' % (
+            primary_key, obj_type, primary_key)
+        server_side_cursor_name = 'swh.journal.%s' % obj_type
+
+        with psycopg2.connect(dsn=self.db_conn) as db:
+            cursor = db.cursor(name=server_side_cursor_name)
+            cursor.execute(query)
+            for o in cursor:
+                yield entry_to_bytes(o[0])
diff --git a/swh/journal/checker.py b/swh/journal/checker.py
new file mode 100644
--- /dev/null
+++ b/swh/journal/checker.py
@@ -0,0 +1,86 @@
+# Copyright (C) 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
+
+"""Module defining journal checker classes.
+
+Those checker goal is to send back all, or missing objects from the
+journal queues.
+
+At the moment, a first naive implementation is the
+SWHSimpleCheckerProducer.  It simply reads the objects from the
+storage and sends every object identifier back to the journal.
+
+"""
+
+from kafka import KafkaProducer
+
+from swh.core.config import SWHConfig
+from .backend import Backend
+from .serializers import value_to_kafka
+
+
+SUPPORTED_OBJECT_TYPES = set([
+    'origin', 'content', 'directory', 'revision', 'release'])
+
+
+class SWHJournalSimpleCheckerProducer(SWHConfig):
+    """Class in charge of reading the storage's objects and sends those
+       back to the publisher queue.
+
+       This is designed to be run periodically.
+
+    """
+    DEFAULT_CONFIG = {
+        'brokers': ('list[str]', ['getty.internal.softwareheritage.org']),
+        'writing_prefix': ('str', 'swh.tmp_journal.new'),
+        'publisher_id': ('str', 'swh.journal.publisher.test'),
+        'object_types': ('list[str]', ['content', 'revision', 'release']),
+        'storage_dbconn': ('str', 'service=swh-dev'),
+    }
+
+    CONFIG_BASE_FILENAME = 'journal/checker'
+
+    def __init__(self, extra_configuration=None):
+        self.config = config = self.parse_config_file()
+        if extra_configuration:
+            config.update(extra_configuration)
+
+        self.object_types = self.config['object_types']
+        for obj_type in self.object_types:
+            if obj_type not in SUPPORTED_OBJECT_TYPES:
+                raise ValueError('The object type %s is not supported. '
+                                 'Possible values are %s' % (
+                                     obj_type, SUPPORTED_OBJECT_TYPES))
+
+        self.storage_backend = Backend(self.config['storage_dbconn'])
+
+        self.producer = KafkaProducer(
+            bootstrap_servers=config['brokers'],
+            value_serializer=value_to_kafka,
+            client_id=config['publisher_id'],
+        )
+
+    def _read_storage(self):
+        """Read all the storage's objects and returns as dict of object_types,
+           set of identifiers.
+
+        """
+        for obj_type in self.object_types:
+            for obj_id in self.storage_backend.fetch(obj_type):
+                yield obj_type, obj_id
+
+    def run(self):
+        """Reads storage's subscribed object types and send them all back to
+           the publisher queue.
+
+        """
+
+        for obj_type, obj_id in self._read_storage():
+            topic = '%s.%s' % (self.config['writing_prefix'], obj_type)
+            self.producer.send(topic, value=obj_id)
+
+
+if __name__ == '__main__':
+    SWHJournalSimpleCheckerProducer().run()