diff --git a/livesync/indico_livesync/cli.py b/livesync/indico_livesync/cli.py
index ca8c337..012cf54 100644
--- a/livesync/indico_livesync/cli.py
+++ b/livesync/indico_livesync/cli.py
@@ -34,7 +34,7 @@ def available_backends():
 def agents():
     """Lists the currently active agents"""
     print('The following LiveSync agents are active:')
-    agent_list = LiveSyncAgent.find().order_by(LiveSyncAgent.backend_name, db.func.lower(LiveSyncAgent.name)).all()
+    agent_list = LiveSyncAgent.query.order_by(LiveSyncAgent.backend_name, db.func.lower(LiveSyncAgent.name)).all()
     table_data = [['ID', 'Name', 'Backend', 'Initial Export', 'Queue']]
     for agent in agent_list:
         initial = (cformat('%{green!}done%{reset}') if agent.initial_data_exported else
@@ -60,7 +60,7 @@ def agents():
 @click.option('--force', is_flag=True, help="Perform export even if it has already been done once.")
 def initial_export(agent_id, force):
     """Performs the initial data export for an agent"""
-    agent = LiveSyncAgent.find_first(id=agent_id)
+    agent = LiveSyncAgent.get(agent_id)
     if agent is None:
         print('No such agent')
         return
@@ -73,7 +73,7 @@ def initial_export(agent_id, force):
         print(cformat('To re-run it, use %{yellow!}--force%{reset}'))
         return
 
-    agent.create_backend().run_initial_export(Event.find(is_deleted=False))
+    agent.create_backend().run_initial_export(Event.query.filter_by(is_deleted=False))
     agent.initial_data_exported = True
     db.session.commit()
 
@@ -84,9 +84,9 @@ def initial_export(agent_id, force):
 def run(agent_id, force=False):
     """Runs the livesync agent"""
     if agent_id is None:
-        agent_list = LiveSyncAgent.find_all()
+        agent_list = LiveSyncAgent.query.all()
     else:
-        agent = LiveSyncAgent.find_first(id=agent_id)
+        agent = LiveSyncAgent.get(agent_id)
         if agent is None:
             print('No such agent')
             return
diff --git a/livesync/indico_livesync/controllers.py b/livesync/indico_livesync/controllers.py
index 18d531b..79eb69d 100644
--- a/livesync/indico_livesync/controllers.py
+++ b/livesync/indico_livesync/controllers.py
@@ -20,7 +20,7 @@ from indico_livesync.models.agents import LiveSyncAgent
 
 
 def extend_plugin_details():
-    agents = LiveSyncAgent.find().order_by(LiveSyncAgent.name, LiveSyncAgent.id).all()
+    agents = LiveSyncAgent.query.order_by(LiveSyncAgent.name, LiveSyncAgent.id).all()
     return render_plugin_template('plugin_details_extra.html', agents=agents, backends=current_plugin.backend_classes)
 
 
diff --git a/livesync/indico_livesync/marcxml.py b/livesync/indico_livesync/marcxml.py
index 6c50a34..0c9d851 100644
--- a/livesync/indico_livesync/marcxml.py
+++ b/livesync/indico_livesync/marcxml.py
@@ -42,7 +42,7 @@ class MARCXMLGenerator:
         self.xml_generator.initXml()
         self.xml_generator.openTag('collection', [['xmlns', 'http://www.loc.gov/MARC21/slim']])
         # This is horrible. but refactoring all the code in the indico core would be just as bad.
-        admin = User.find_first(is_admin=True)
+        admin = User.query.filter_by(is_admin=True).first()
         self.output_generator = outputGenerator(admin, self.xml_generator)
 
     def safe_add_object(self, obj, deleted=False):
diff --git a/livesync/indico_livesync/simplify.py b/livesync/indico_livesync/simplify.py
index e1f7cf1..b17180d 100644
--- a/livesync/indico_livesync/simplify.py
+++ b/livesync/indico_livesync/simplify.py
@@ -82,19 +82,19 @@ def _process_cascaded_category_contents(records):
 
     # Protection changes are handled differently, as there may not be the need to re-generate the record
     if category_prot_records:
-        for categ in Category.find(Category.id.in_(category_prot_records)):
+        for categ in Category.query.filter(Category.id.in_(category_prot_records)):
             cte = categ.get_protection_parent_cte()
             # Update only children that inherit
             inheriting_categ_children = (Event.query
                                          .join(cte, db.and_((Event.category_id == cte.c.id),
                                                             (cte.c.protection_parent == categ.id))))
-            inheriting_direct_children = Event.find((Event.category_id == categ.id) & Event.is_inheriting)
+            inheriting_direct_children = Event.query.filter((Event.category_id == categ.id) & Event.is_inheriting)
 
             changed_events.update(itertools.chain(inheriting_direct_children, inheriting_categ_children))
 
     # Add move operations and explicitly-passed event records
     if category_move_records:
-        changed_events.update(Event.find(Event.category_chain_overlaps(category_move_records)))
+        changed_events.update(Event.query.filter(Event.category_chain_overlaps(category_move_records)))
 
     yield from _process_cascaded_event_contents(records, additional_events=changed_events)
 
@@ -119,14 +119,14 @@ def _process_cascaded_event_contents(records, additional_events=None):
     event_records = {rec.event_id for rec in records if rec.type == EntryType.event}
 
     if event_records:
-        changed_events.update(Event.find(Event.id.in_(event_records)))
+        changed_events.update(Event.query.filter(Event.id.in_(event_records)))
 
     yield from changed_events
 
     # Sessions are added (explicitly changed only, since they don't need to be sent anywhere)
     if session_records:
-        changed_contributions.update(Contribution
-                                     .find(Contribution.session_id.in_(session_records), ~Contribution.is_deleted))
+        changed_contributions.update(Contribution.query
+                                     .filter(Contribution.session_id.in_(session_records), ~Contribution.is_deleted))
 
     # Contributions are added (implictly + explicitly changed)
     changed_event_ids = {ev.id for ev in changed_events}
@@ -134,7 +134,7 @@ def _process_cascaded_event_contents(records, additional_events=None):
     condition = Contribution.event_id.in_(changed_event_ids) & ~Contribution.is_deleted
     if contribution_records:
         condition = db.or_(condition, Contribution.id.in_(contribution_records))
-    contrib_query = Contribution.find(condition).options(joinedload('subcontributions'))
+    contrib_query = Contribution.query.filter(condition).options(joinedload('subcontributions'))
 
     for contribution in contrib_query:
         yield contribution
@@ -142,5 +142,5 @@ def _process_cascaded_event_contents(records, additional_events=None):
 
     # Same for subcontributions
     if subcontribution_records:
-        changed_subcontributions.update(SubContribution.find(SubContribution.id.in_(subcontribution_records)))
+        changed_subcontributions.update(SubContribution.query.filter(SubContribution.id.in_(subcontribution_records)))
     yield from changed_subcontributions
diff --git a/livesync/indico_livesync/task.py b/livesync/indico_livesync/task.py
index 73c1ac7..7a2f254 100644
--- a/livesync/indico_livesync/task.py
+++ b/livesync/indico_livesync/task.py
@@ -18,7 +18,7 @@ from indico_livesync.util import clean_old_entries
 def scheduled_update():
     from indico_livesync.plugin import LiveSyncPlugin
     clean_old_entries()
-    for agent in LiveSyncAgent.find_all():
+    for agent in LiveSyncAgent.query.all():
         if agent.backend is None:
             LiveSyncPlugin.logger.warning('Skipping agent %s; backend not found', agent.name)
             continue
diff --git a/livesync/indico_livesync/util.py b/livesync/indico_livesync/util.py
index e65c48a..18324bd 100644
--- a/livesync/indico_livesync/util.py
+++ b/livesync/indico_livesync/util.py
@@ -63,8 +63,9 @@ def clean_old_entries():
     if not queue_entry_ttl:
         return
     expire_threshold = now_utc() - timedelta(days=queue_entry_ttl)
-    LiveSyncQueueEntry.find(LiveSyncQueueEntry.processed,
-                            LiveSyncQueueEntry.timestamp < expire_threshold).delete(synchronize_session='fetch')
+    query = LiveSyncQueueEntry.query.filter(LiveSyncQueueEntry.processed,
+                                            LiveSyncQueueEntry.timestamp < expire_threshold)
+    query.delete(synchronize_session='fetch')
 
 
 @memoize_request
diff --git a/livesync/tests/util_test.py b/livesync/tests/util_test.py
index 440e6d7..281ca0e 100644
--- a/livesync/tests/util_test.py
+++ b/livesync/tests/util_test.py
@@ -24,13 +24,13 @@ def test_clean_old_entries(dummy_event, db, dummy_agent):
     db.session.flush()
     # Nothing deleted with the setting's default value
     clean_old_entries()
-    assert LiveSyncQueueEntry.find().count() == 20
+    assert LiveSyncQueueEntry.query.count() == 20
     # Nothing deleted when explicitly set to 0 (which is the default)
     LiveSyncPlugin.settings.set('queue_entry_ttl', 0)
     clean_old_entries()
-    assert LiveSyncQueueEntry.find().count() == 20
+    assert LiveSyncQueueEntry.query.count() == 20
     # Only the correct entries deleted, and no unprocessed ones
     LiveSyncPlugin.settings.set('queue_entry_ttl', 3)
     clean_old_entries()
-    assert LiveSyncQueueEntry.find(processed=False).count() == 10
-    assert LiveSyncQueueEntry.find(processed=True).count() == 3
+    assert LiveSyncQueueEntry.query.filter_by(processed=False).count() == 10
+    assert LiveSyncQueueEntry.query.filter_by(processed=True).count() == 3
diff --git a/payment_paypal/indico_payment_paypal/controllers.py b/payment_paypal/indico_payment_paypal/controllers.py
index e508315..82cfdbc 100644
--- a/payment_paypal/indico_payment_paypal/controllers.py
+++ b/payment_paypal/indico_payment_paypal/controllers.py
@@ -37,7 +37,7 @@ class RHPaypalIPN(RH):
 
     def _process_args(self):
         self.token = request.args['token']
-        self.registration = Registration.find_first(uuid=self.token)
+        self.registration = Registration.query.filter_by(uuid=self.token).first()
         if not self.registration:
             raise BadRequest
 
diff --git a/piwik/indico_piwik/plugin.py b/piwik/indico_piwik/plugin.py
index dc620ce..460e268 100644
--- a/piwik/indico_piwik/plugin.py
+++ b/piwik/indico_piwik/plugin.py
@@ -101,7 +101,7 @@ class PiwikPlugin(IndicoPlugin):
             params['event_id'] = request.view_args['confId']
             contrib_id = request.view_args.get('contrib_id')
             if contrib_id is not None and str(contrib_id).isdigit():
-                contribution = Contribution.find_first(event_id=params['event_id'], id=contrib_id)
+                contribution = Contribution.query.filter_by(event_id=params['event_id'], id=contrib_id).first()
                 if contribution:
                     cid = (contribution.legacy_mapping.legacy_contribution_id if contribution.legacy_mapping
                            else contribution.id)
diff --git a/previewer_jupyter/indico_previewer_jupyter/controllers.py b/previewer_jupyter/indico_previewer_jupyter/controllers.py
index 8641549..cdb2ebc 100644
--- a/previewer_jupyter/indico_previewer_jupyter/controllers.py
+++ b/previewer_jupyter/indico_previewer_jupyter/controllers.py
@@ -25,7 +25,7 @@ class RHEventPreviewIPyNB(RH):
             raise Forbidden
 
     def _process_args(self):
-        self.attachment = Attachment.find_one(id=request.view_args['attachment_id'], is_deleted=False)
+        self.attachment = Attachment.query.filter_by(id=request.view_args['attachment_id'], is_deleted=False).one()
 
     def _process(self):
         config = Config()
diff --git a/vc_vidyo/indico_vc_vidyo/cli.py b/vc_vidyo/indico_vc_vidyo/cli.py
index 6ea1633..aadd383 100644
--- a/vc_vidyo/indico_vc_vidyo/cli.py
+++ b/vc_vidyo/indico_vc_vidyo/cli.py
@@ -22,7 +22,7 @@ def cli():
 def rooms(status=None):
     """Lists all Vidyo rooms"""
 
-    room_query = VCRoom.find(type='vidyo')
+    room_query = VCRoom.query.filter_by(type='vidyo')
     table_data = [['ID', 'Name', 'Status', 'Vidyo ID', 'Extension']]
 
     if status:
diff --git a/vc_vidyo/indico_vc_vidyo/plugin.py b/vc_vidyo/indico_vc_vidyo/plugin.py
index 849816b..6c28e4e 100644
--- a/vc_vidyo/indico_vc_vidyo/plugin.py
+++ b/vc_vidyo/indico_vc_vidyo/plugin.py
@@ -322,7 +322,7 @@ class VidyoPlugin(VCPluginMixin, IndicoPlugin):
 
     def _merge_users(self, target, source, **kwargs):
         super()._merge_users(target, source, **kwargs)
-        for ext in VidyoExtension.find(owned_by_user=source):
+        for ext in VidyoExtension.query.filter_by(owned_by_user=source):
             ext.owned_by_user = target
             flag_modified(ext.vc_room, 'data')
 
diff --git a/vc_vidyo/indico_vc_vidyo/task.py b/vc_vidyo/indico_vc_vidyo/task.py
index 21f184e..d0e94ea 100644
--- a/vc_vidyo/indico_vc_vidyo/task.py
+++ b/vc_vidyo/indico_vc_vidyo/task.py
@@ -34,7 +34,7 @@ def find_old_vidyo_rooms(max_room_event_age):
                      .group_by(VCRoom.id))
 
     # non-deleted rooms with no recent associations
-    return VCRoom.find_all(VCRoom.status != VCRoomStatus.deleted, ~VCRoom.id.in_(recently_used))
+    return VCRoom.query.filter(VCRoom.status != VCRoomStatus.deleted, ~VCRoom.id.in_(recently_used)).all()
 
 
 def notify_owner(plugin, vc_room):
diff --git a/vc_vidyo/indico_vc_vidyo/util.py b/vc_vidyo/indico_vc_vidyo/util.py
index b59d352..bd984eb 100644
--- a/vc_vidyo/indico_vc_vidyo/util.py
+++ b/vc_vidyo/indico_vc_vidyo/util.py
@@ -33,7 +33,7 @@ def iter_user_identities(user):
 def get_user_from_identifier(settings, identifier):
     """Get an actual User object from an identifier"""
     providers = list(auth.strip() for auth in settings.get('authenticators').split(','))
-    identities = Identity.find_all(Identity.provider.in_(providers), Identity.identifier == identifier)
+    identities = Identity.query.filter(Identity.provider.in_(providers), Identity.identifier == identifier).all()
     if identities:
         return sorted(identities, key=lambda x: providers.index(x.provider))[0].user
     for provider in providers:
@@ -48,7 +48,7 @@ def get_user_from_identifier(settings, identifier):
         emails = {email.lower() for email in identity_info.data.getlist('email') if email}
         if not emails:
             continue
-        user = User.find_first(~User.is_deleted, User.all_emails.in_(list(emails)))
+        user = User.query.filter(~User.is_deleted, User.all_emails.in_(list(emails))).first()
         if user:
             return user