diff --git a/.gitignore b/.gitignore
index f5fc2ae..898ba80 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,8 +1,9 @@
 *.pyc
 *.sw?
 *~
 .coverage
 .eggs/
 __pycache__
 *.egg-info/
-version.txt
\ No newline at end of file
+version.txt
+/.hypothesis/
diff --git a/debian/control b/debian/control
index 5e4d9bf..6a6d5ed 100644
--- a/debian/control
+++ b/debian/control
@@ -1,25 +1,26 @@
 Source: swh-scheduler
 Maintainer: Software Heritage developers <swh-devel@inria.fr>
 Section: python
 Priority: optional
 Build-Depends: debhelper (>= 9),
                dh-python (>= 2),
                python3-all,
                python3-arrow,
                python3-celery,
                python3-click,
                python3-elasticsearch (>= 5.4.0),
                python3-flask,
+               python3-hypothesis,
                python3-kombu,
                python3-nose,
                python3-psycopg2,
                python3-setuptools,
                python3-swh.core (>= 0.0.38~),
                python3-vcversioner
 Standards-Version: 3.9.6
 Homepage: https://forge.softwareheritage.org/diffusion/DSCH/
 
 Package: python3-swh.scheduler
 Architecture: all
 Depends: python3-swh.core (>= 0.0.38~), ${misc:Depends}, ${python3:Depends}
 Description: Software Heritage Scheduler
diff --git a/requirements.txt b/requirements.txt
index 1af0cad..0bb53f8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,12 +1,13 @@
 # Add here external Python modules dependencies, one per line. Module names
 # should match https://pypi.python.org/pypi names. For the full spec or
 # dependency lines, see https://pip.readthedocs.org/en/1.1/requirements.html
 
 arrow
 celery
 Click
 elasticsearch>5.4
 flask
 kombu
 psycopg2
 vcversioner
+hypothesis
diff --git a/swh/scheduler/tests/test_events.py b/swh/scheduler/tests/test_events.py
new file mode 100644
index 0000000..f62cbcd
--- /dev/null
+++ b/swh/scheduler/tests/test_events.py
@@ -0,0 +1,54 @@
+# Copyright (C) 2018  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 unittest
+
+from nose.tools import istest
+
+from swh.scheduler.updater.events import SWHEvent, LISTENED_EVENTS
+from hypothesis import given
+from hypothesis.strategies import one_of, text, just, sampled_from
+
+
+def event_values_ko():
+    return {
+        'repos', 'org_members', 'teamadd', 'geo_cache',
+        'follow', 'issue_comments', 'followers', 'forks', 'pagebuild',
+        'pullrequest', 'pull_requests', 'commit_comments', 'watch', 'fork',
+        'forkapply', 'commits', 'release', 'gollum', 'membership', 'watchers',
+        'pullrequestreviewcomment', 'deployment', 'issuecomment', 'status',
+        'repo_labels', 'issue_events', 'commitcomment', 'issues', 'member',
+        'users', 'download', 'repo_collaborators', 'repository',
+        'deploymentstatus', 'pull_request_comments', 'gist'
+    }
+
+
+class EventTest(unittest.TestCase):
+    def _make_event(self, event_name):
+        return {
+            'evt': event_name,
+            'url': 'something'
+        }
+
+    @istest
+    @given(sampled_from(LISTENED_EVENTS))
+    def check_ok(self, event_name):
+        evt = self._make_event(event_name)
+        self.assertTrue(SWHEvent(evt).check())
+
+    @istest
+    @given(text())
+    def check_with_noisy_event_should_be_ko(self, event_name):
+        if event_name in LISTENED_EVENTS:
+            # just in generation generates a real and correct name, skip it
+            return
+        evt = self._make_event(event_name)
+        self.assertFalse(SWHEvent(evt).check())
+
+    @istest
+    @given(one_of(map(just, event_values_ko())))
+    def check_ko(self, event_name):
+        evt = self._make_event(event_name)
+        self.assertFalse(SWHEvent(evt).check())
diff --git a/swh/scheduler/updater/events.py b/swh/scheduler/updater/events.py
new file mode 100644
index 0000000..3e660bf
--- /dev/null
+++ b/swh/scheduler/updater/events.py
@@ -0,0 +1,39 @@
+# Copyright (C) 2018  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
+
+
+LISTENED_EVENTS = [
+    'create',
+    'delete',
+    'public',
+    'push'
+]
+
+
+class SWHEvent:
+    """SWH's interesting event (resulting in an origin update)
+
+    """
+    def __init__(self, evt):
+        self.event = evt
+
+    def check(self):
+        return 'evt' in self.event and self.event['evt'] in LISTENED_EVENTS
+
+    def __str__(self):
+        return {
+            'evt': self.event['evt'],
+            'url': self.event['url']
+        }
+
+
+class SWHPublisher:
+    def process(self):
+        pass
+
+
+class SWHSubscriber:
+    def process(self):
+        pass