diff --git a/canaille/app/flask.py b/canaille/app/flask.py
index de96c000..134d656d 100644
--- a/canaille/app/flask.py
+++ b/canaille/app/flask.py
@@ -20,7 +20,7 @@ def current_user():
         return g.user
 
     for user_id in session.get("user_id", [])[::-1]:
-        user = models.User.get(user_id)
+        user = current_app.backend.instance.get(models.User, user_id)
         if user and (
             not current_app.backend.has_account_lockability() or not user.locked
         ):
@@ -147,7 +147,7 @@ def model_converter(model):
 
         def to_python(self, identifier):
             current_app.backend.setup()
-            instance = model.get(identifier)
+            instance = current_app.backend.get(model, identifier)
             if self.required and not instance:
                 abort(404)
 
diff --git a/canaille/app/forms.py b/canaille/app/forms.py
index 8d65d30b..65db468e 100644
--- a/canaille/app/forms.py
+++ b/canaille/app/forms.py
@@ -260,7 +260,9 @@ class IDToModel:
 
     def __call__(self, data):
         model = getattr(models, self.model_name)
-        instance = data if isinstance(data, model) else model.get(data)
+        instance = (
+            data if isinstance(data, model) else BaseBackend.instance.get(model, data)
+        )
         if instance:
             return instance
 
diff --git a/canaille/backends/__init__.py b/canaille/backends/__init__.py
index b2dd5e76..a7bfcad1 100644
--- a/canaille/backends/__init__.py
+++ b/canaille/backends/__init__.py
@@ -80,6 +80,11 @@ class BaseBackend:
         attribute values loosely be matched."""
         raise NotImplementedError()
 
+    def get(self, model, identifier=None, **kwargs):
+        """Works like :meth:`~canaille.backends.BaseBackend.query` but return
+        only one element or :py:data:`None` if no item is matching."""
+        raise NotImplementedError()
+
     def check_user_password(self, user, password: str) -> bool:
         """Check if the password matches the user password in the database."""
         raise NotImplementedError()
diff --git a/canaille/backends/ldap/backend.py b/canaille/backends/ldap/backend.py
index 9630d902..e48f51e1 100644
--- a/canaille/backends/ldap/backend.py
+++ b/canaille/backends/ldap/backend.py
@@ -202,7 +202,7 @@ class Backend(BaseBackend):
             if login
             else None
         )
-        return User.get(filter=filter)
+        return self.get(User, filter=filter)
 
     def check_user_password(self, user, password):
         conn = ldap.initialize(current_app.config["CANAILLE_LDAP"]["URI"])
@@ -311,6 +311,19 @@ class Backend(BaseBackend):
         )
         return self.query(model, filter=filter, **kwargs)
 
+    def get(self, model, identifier=None, /, **kwargs):
+        try:
+            return self.query(model, identifier, **kwargs)[0]
+        except (IndexError, ldap.NO_SUCH_OBJECT):
+            if identifier and model.base:
+                return (
+                    self.get(model, **{model.identifier_attribute: identifier})
+                    or self.get(model, id=identifier)
+                    or None
+                )
+
+            return None
+
 
 def setup_ldap_models(config):
     from canaille.app import models
diff --git a/canaille/backends/ldap/ldapobject.py b/canaille/backends/ldap/ldapobject.py
index 7e2688bf..2eacee7b 100644
--- a/canaille/backends/ldap/ldapobject.py
+++ b/canaille/backends/ldap/ldapobject.py
@@ -4,7 +4,6 @@ import ldap.dn
 import ldap.filter
 from ldap.controls.readentry import PostReadControl
 
-from canaille.backends import BaseBackend
 from canaille.backends.models import BackendModel
 
 from .backend import Backend
@@ -226,20 +225,6 @@ class LDAPObject(BackendModel, metaclass=LDAPObjectMetaclass):
 
         return cls._attribute_type_by_name
 
-    @classmethod
-    def get(cls, identifier=None, /, **kwargs):
-        try:
-            return BaseBackend.instance.query(cls, identifier, **kwargs)[0]
-        except (IndexError, ldap.NO_SUCH_OBJECT):
-            if identifier and cls.base:
-                return (
-                    cls.get(**{cls.identifier_attribute: identifier})
-                    or cls.get(id=identifier)
-                    or None
-                )
-
-            return None
-
     @classmethod
     def update_ldap_attributes(cls):
         all_object_classes = cls.ldap_object_classes()
diff --git a/canaille/backends/ldap/utils.py b/canaille/backends/ldap/utils.py
index 63186976..9cc13a61 100644
--- a/canaille/backends/ldap/utils.py
+++ b/canaille/backends/ldap/utils.py
@@ -1,6 +1,8 @@
 import datetime
 from enum import Enum
 
+from canaille.backends import BaseBackend
+
 LDAP_NULL_DATE = "000001010000Z"
 
 
@@ -50,7 +52,7 @@ def ldap_to_python(value, syntax):
         return value.decode("utf-8").upper() == "TRUE"
 
     if syntax == Syntax.DISTINGUISHED_NAME:
-        return LDAPObject.get(value.decode("utf-8"))
+        return BaseBackend.instance.get(LDAPObject, value.decode("utf-8"))
 
     return value.decode("utf-8")
 
diff --git a/canaille/backends/memory/backend.py b/canaille/backends/memory/backend.py
index 4b24da2e..fbeb3020 100644
--- a/canaille/backends/memory/backend.py
+++ b/canaille/backends/memory/backend.py
@@ -26,7 +26,7 @@ class Backend(BaseBackend):
     def get_user_from_login(self, login):
         from .models import User
 
-        return User.get(user_name=login)
+        return self.get(User, user_name=login)
 
     def check_user_password(self, user, password):
         if password != user.password:
@@ -80,3 +80,14 @@ class Backend(BaseBackend):
                 if isinstance(value, str)
             )
         ]
+
+    def get(self, model, identifier=None, /, **kwargs):
+        if identifier:
+            return (
+                self.get(model, **{model.identifier_attribute: identifier})
+                or self.get(model, id=identifier)
+                or None
+            )
+
+        results = self.query(model, **kwargs)
+        return results[0] if results else None
diff --git a/canaille/backends/memory/models.py b/canaille/backends/memory/models.py
index 59f8630e..41ebb8ce 100644
--- a/canaille/backends/memory/models.py
+++ b/canaille/backends/memory/models.py
@@ -36,18 +36,6 @@ class MemoryModel(BackendModel):
             class_name or cls.__name__, {}
         ).setdefault(attribute, {})
 
-    @classmethod
-    def get(cls, identifier=None, /, **kwargs):
-        if identifier:
-            return (
-                cls.get(**{cls.identifier_attribute: identifier})
-                or cls.get(id=identifier)
-                or None
-            )
-
-        results = BaseBackend.instance.query(cls, **kwargs)
-        return results[0] if results else None
-
     @classmethod
     def listify(cls, value):
         return value if isinstance(value, list) else [value]
@@ -75,7 +63,7 @@ class MemoryModel(BackendModel):
         model, _ = cls.get_model_annotations(attribute_name)
         if model and not isinstance(value, model):
             backend_model = getattr(models, model.__name__)
-            return backend_model.get(id=value)
+            return BaseBackend.instance.get(backend_model, id=value)
 
         return value
 
@@ -166,7 +154,7 @@ class MemoryModel(BackendModel):
         del self.index()[self.id]
 
     def reload(self):
-        self._state = self.__class__.get(id=self.id)._state
+        self._state = BaseBackend.instance.get(self.__class__, id=self.id)._state
         self._cache = {}
 
     def __eq__(self, other):
@@ -174,7 +162,7 @@ class MemoryModel(BackendModel):
             return False
 
         if not isinstance(other, MemoryModel):
-            return self == self.__class__.get(id=other)
+            return self == BaseBackend.instance.get(self.__class__, id=other)
 
         return self._state == other._state
 
diff --git a/canaille/backends/models.py b/canaille/backends/models.py
index 3a954b0d..3e8998b6 100644
--- a/canaille/backends/models.py
+++ b/canaille/backends/models.py
@@ -11,6 +11,7 @@ from typing import get_type_hints
 
 from canaille.app import classproperty
 from canaille.app import models
+from canaille.backends import BaseBackend
 
 
 class Model:
@@ -87,12 +88,6 @@ class BackendModel:
     implemented for every model and for every backend.
     """
 
-    @classmethod
-    def get(cls, identifier=None, **kwargs):
-        """Works like :meth:`~canaille.backends.BaseBackend.query` but return
-        only one element or :py:data:`None` if no item is matching."""
-        raise NotImplementedError()
-
     def save(self):
         """Validate the current modifications in the database."""
         raise NotImplementedError()
@@ -175,7 +170,7 @@ class BackendModel:
 
             backend_model = getattr(models, model.__name__)
 
-            if instance := backend_model.get(value):
+            if instance := BaseBackend.instance.get(backend_model, value):
                 filter[attribute] = instance
 
         return all(
diff --git a/canaille/backends/sql/backend.py b/canaille/backends/sql/backend.py
index 76f867a5..39866386 100644
--- a/canaille/backends/sql/backend.py
+++ b/canaille/backends/sql/backend.py
@@ -53,7 +53,7 @@ class Backend(BaseBackend):
     def get_user_from_login(self, login):
         from .models import User
 
-        return User.get(user_name=login)
+        return self.get(User, user_name=login)
 
     def check_user_password(self, user, password):
         if password != user.password:
@@ -90,3 +90,19 @@ class Backend(BaseBackend):
         )
 
         return self.db_session.execute(select(model).filter(filter)).scalars().all()
+
+    def get(self, model, identifier=None, /, **kwargs):
+        if identifier:
+            return (
+                self.get(model, **{model.identifier_attribute: identifier})
+                or self.get(model, id=identifier)
+                or None
+            )
+
+        filter = [
+            model.attribute_filter(attribute_name, expected_value)
+            for attribute_name, expected_value in kwargs.items()
+        ]
+        return Backend.instance.db_session.execute(
+            select(model).filter(*filter)
+        ).scalar_one_or_none()
diff --git a/canaille/backends/sql/models.py b/canaille/backends/sql/models.py
index 9bd78445..bd14f85a 100644
--- a/canaille/backends/sql/models.py
+++ b/canaille/backends/sql/models.py
@@ -11,7 +11,6 @@ from sqlalchemy import LargeBinary
 from sqlalchemy import String
 from sqlalchemy import Table
 from sqlalchemy import or_
-from sqlalchemy import select
 from sqlalchemy.orm import Mapped
 from sqlalchemy.orm import mapped_column
 from sqlalchemy.orm import relationship
@@ -48,23 +47,6 @@ class SqlAlchemyModel(BackendModel):
 
         return getattr(cls, name) == value
 
-    @classmethod
-    def get(cls, identifier=None, /, **kwargs):
-        if identifier:
-            return (
-                cls.get(**{cls.identifier_attribute: identifier})
-                or cls.get(id=identifier)
-                or None
-            )
-
-        filter = [
-            cls.attribute_filter(attribute_name, expected_value)
-            for attribute_name, expected_value in kwargs.items()
-        ]
-        return Backend.instance.db_session.execute(
-            select(cls).filter(*filter)
-        ).scalar_one_or_none()
-
     def save(self):
         self.last_modified = datetime.datetime.now(datetime.timezone.utc).replace(
             microsecond=0
diff --git a/canaille/core/endpoints/account.py b/canaille/core/endpoints/account.py
index 708a5dcd..a34af0da 100644
--- a/canaille/core/endpoints/account.py
+++ b/canaille/core/endpoints/account.py
@@ -257,7 +257,9 @@ def registration(data=None, hash=None):
             )
             return redirect(url_for("core.account.index"))
 
-        if payload.user_name and models.User.get(user_name=payload.user_name):
+        if payload.user_name and BaseBackend.instance.get(
+            models.User, user_name=payload.user_name
+        ):
             flash(
                 _("Your account has already been created."),
                 "error",
@@ -282,7 +284,10 @@ def registration(data=None, hash=None):
         data = {
             "user_name": payload.user_name,
             "emails": [payload.email],
-            "groups": [models.Group.get(id=group_id) for group_id in payload.groups],
+            "groups": [
+                BaseBackend.instance.get(models.Group, id=group_id)
+                for group_id in payload.groups
+            ],
         }
 
     has_smtp = "SMTP" in current_app.config["CANAILLE"]
@@ -376,7 +381,7 @@ def email_confirmation(data, hash):
         )
         return redirect(url_for("core.account.index"))
 
-    user = models.User.get(confirmation_obj.identifier)
+    user = BaseBackend.instance.get(models.User, confirmation_obj.identifier)
     if not user:
         flash(
             _("The email confirmation link that brought you here is invalid."),
diff --git a/canaille/core/endpoints/forms.py b/canaille/core/endpoints/forms.py
index 5deb8711..26b6ae57 100644
--- a/canaille/core/endpoints/forms.py
+++ b/canaille/core/endpoints/forms.py
@@ -24,7 +24,7 @@ MINIMUM_PASSWORD_LENGTH = 8
 
 
 def unique_user_name(form, field):
-    if models.User.get(user_name=field.data) and (
+    if BaseBackend.instance.get(models.User, user_name=field.data) and (
         not getattr(form, "user", None) or form.user.user_name != field.data
     ):
         raise wtforms.ValidationError(
@@ -33,7 +33,7 @@ def unique_user_name(form, field):
 
 
 def unique_email(form, field):
-    if models.User.get(emails=field.data) and (
+    if BaseBackend.instance.get(models.User, emails=field.data) and (
         not getattr(form, "user", None) or field.data not in form.user.emails
     ):
         raise wtforms.ValidationError(
@@ -42,7 +42,7 @@ def unique_email(form, field):
 
 
 def unique_group(form, field):
-    if models.Group.get(display_name=field.data):
+    if BaseBackend.instance.get(models.Group, display_name=field.data):
         raise wtforms.ValidationError(
             _("The group '{group}' already exists").format(group=field.data)
         )
diff --git a/canaille/core/models.py b/canaille/core/models.py
index caad8ae9..1e2c0652 100644
--- a/canaille/core/models.py
+++ b/canaille/core/models.py
@@ -258,12 +258,12 @@ class User(Model):
     def preferred_email(self):
         return self.emails[0] if self.emails else None
 
-    def __getattr__(self, name):
+    def __getattribute__(self, name):
         prefix = "can_"
         if name.startswith(prefix) and name != "can_read":
             return self.can(name[len(prefix) :])
 
-        return super().__getattr__(name)
+        return super().__getattribute__(name)
 
     def can(self, *permissions: Permission):
         """Wether or not the user has the
diff --git a/canaille/oidc/endpoints/consents.py b/canaille/oidc/endpoints/consents.py
index b5fdd35a..1dcff0be 100644
--- a/canaille/oidc/endpoints/consents.py
+++ b/canaille/oidc/endpoints/consents.py
@@ -108,7 +108,7 @@ def revoke_preconsent(user, client):
         flash(_("Could not revoke this access"), "error")
         return redirect(url_for("oidc.consents.consents"))
 
-    consent = models.Consent.get(client=client, subject=user)
+    consent = BaseBackend.instance.get(models.Consent, client=client, subject=user)
     if consent:
         return redirect(url_for("oidc.consents.revoke", consent=consent))
 
diff --git a/canaille/oidc/endpoints/oauth.py b/canaille/oidc/endpoints/oauth.py
index af1bb400..9810993c 100644
--- a/canaille/oidc/endpoints/oauth.py
+++ b/canaille/oidc/endpoints/oauth.py
@@ -50,7 +50,9 @@ def authorize():
         request.form.to_dict(flat=False),
     )
 
-    client = models.Client.get(client_id=request.args["client_id"])
+    client = BaseBackend.instance.get(
+        models.Client, client_id=request.args["client_id"]
+    )
     user = current_user()
 
     if response := authorize_guards(client):
@@ -276,7 +278,7 @@ def end_session():
     valid_uris = []
 
     if "client_id" in data:
-        client = models.Client.get(client_id=data["client_id"])
+        client = BaseBackend.instance.get(models.Client, client_id=data["client_id"])
         if client:
             valid_uris = client.post_logout_redirect_uris
 
@@ -328,7 +330,7 @@ def end_session():
                 else [id_token["aud"]]
             )
             for client_id in client_ids:
-                client = models.Client.get(client_id=client_id)
+                client = BaseBackend.instance.get(models.Client, client_id=client_id)
                 if client:
                     valid_uris.extend(client.post_logout_redirect_uris or [])
 
diff --git a/canaille/oidc/oauth.py b/canaille/oidc/oauth.py
index 1cc7a670..a07efb6e 100644
--- a/canaille/oidc/oauth.py
+++ b/canaille/oidc/oauth.py
@@ -111,7 +111,7 @@ def openid_configuration():
 
 
 def exists_nonce(nonce, req):
-    client = models.Client.get(id=req.client_id)
+    client = BaseBackend.instance.get(models.Client, id=req.client_id)
     exists = BaseBackend.instance.query(
         models.AuthorizationCode, client=client, nonce=nonce
     )
@@ -334,7 +334,7 @@ class OpenIDHybridGrant(_OpenIDHybridGrant):
 
 
 def query_client(client_id):
-    return models.Client.get(client_id=client_id)
+    return BaseBackend.instance.get(models.Client, client_id=client_id)
 
 
 def save_token(token, request):
@@ -356,20 +356,20 @@ def save_token(token, request):
 
 class BearerTokenValidator(_BearerTokenValidator):
     def authenticate_token(self, token_string):
-        return models.Token.get(access_token=token_string)
+        return BaseBackend.instance.get(models.Token, access_token=token_string)
 
 
 def query_token(token, token_type_hint):
     if token_type_hint == "access_token":
-        return models.Token.get(access_token=token)
+        return BaseBackend.instance.get(models.Token, access_token=token)
     elif token_type_hint == "refresh_token":
-        return models.Token.get(refresh_token=token)
+        return BaseBackend.instance.get(models.Token, refresh_token=token)
 
-    item = models.Token.get(access_token=token)
+    item = BaseBackend.instance.get(models.Token, access_token=token)
     if item:
         return item
 
-    item = models.Token.get(refresh_token=token)
+    item = BaseBackend.instance.get(models.Token, refresh_token=token)
     if item:
         return item
 
@@ -472,7 +472,7 @@ class ClientRegistrationEndpoint(ClientManagementMixin, _ClientRegistrationEndpo
 class ClientConfigurationEndpoint(ClientManagementMixin, _ClientConfigurationEndpoint):
     def authenticate_client(self, request):
         client_id = request.uri.split("/")[-1]
-        return models.Client.get(client_id=client_id)
+        return BaseBackend.instance.get(models.Client, client_id=client_id)
 
     def revoke_access_token(self, request, token):
         pass
diff --git a/tests/backends/ldap/test_object_class.py b/tests/backends/ldap/test_object_class.py
index 84844c02..b7863459 100644
--- a/tests/backends/ldap/test_object_class.py
+++ b/tests/backends/ldap/test_object_class.py
@@ -7,7 +7,7 @@ def test_guess_object_from_dn(backend, testclient, foo_group):
     foo_group.members = [foo_group]
     foo_group.save()
     dn = foo_group.dn
-    g = LDAPObject.get(dn)
+    g = backend.get(LDAPObject, dn)
     assert isinstance(g, models.Group)
     assert g == foo_group
     assert g.display_name == foo_group.display_name
@@ -21,9 +21,9 @@ def test_object_class_update(backend, testclient):
     user1.save()
 
     assert set(user1.get_ldap_attribute("objectClass")) == {"inetOrgPerson"}
-    assert set(models.User.get(id=user1.id).get_ldap_attribute("objectClass")) == {
-        "inetOrgPerson"
-    }
+    assert set(
+        backend.get(models.User, id=user1.id).get_ldap_attribute("objectClass")
+    ) == {"inetOrgPerson"}
 
     testclient.app.config["CANAILLE_LDAP"]["USER_CLASS"] = [
         "inetOrgPerson",
@@ -38,12 +38,14 @@ def test_object_class_update(backend, testclient):
         "inetOrgPerson",
         "extensibleObject",
     }
-    assert set(models.User.get(id=user2.id).get_ldap_attribute("objectClass")) == {
+    assert set(
+        backend.get(models.User, id=user2.id).get_ldap_attribute("objectClass")
+    ) == {
         "inetOrgPerson",
         "extensibleObject",
     }
 
-    user1 = models.User.get(id=user1.id)
+    user1 = backend.get(models.User, id=user1.id)
     assert user1.get_ldap_attribute("objectClass") == ["inetOrgPerson"]
 
     user1.save()
@@ -51,7 +53,9 @@ def test_object_class_update(backend, testclient):
         "inetOrgPerson",
         "extensibleObject",
     }
-    assert set(models.User.get(id=user1.id).get_ldap_attribute("objectClass")) == {
+    assert set(
+        backend.get(models.User, id=user1.id).get_ldap_attribute("objectClass")
+    ) == {
         "inetOrgPerson",
         "extensibleObject",
     }
diff --git a/tests/backends/ldap/test_utils.py b/tests/backends/ldap/test_utils.py
index faec2a55..36b87084 100644
--- a/tests/backends/ldap/test_utils.py
+++ b/tests/backends/ldap/test_utils.py
@@ -27,7 +27,7 @@ def test_object_creation(app, backend):
     user.save()
     assert user.exists
 
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.exists
 
     user.delete()
@@ -52,9 +52,9 @@ def test_dn_when_leading_space_in_id_attribute(testclient, backend):
     assert ldap.dn.is_dn(dn)
     assert ldap.dn.dn2str(ldap.dn.str2dn(dn)) == dn
 
-    assert user == models.User.get(user.user_name)
-    assert user == models.User.get(user_name=user.user_name)
-    assert user == models.User.get(dn)
+    assert user == backend.get(models.User, user.user_name)
+    assert user == backend.get(models.User, user_name=user.user_name)
+    assert user == backend.get(models.User, dn)
 
     user.delete()
 
@@ -73,9 +73,9 @@ def test_special_chars_in_rdn(testclient, backend):
     assert ldap.dn.dn2str(ldap.dn.str2dn(dn)) == dn
     assert dn == "uid=\\#user,ou=users,dc=mydomain,dc=tld"
 
-    assert user == models.User.get(user.user_name)
-    assert user == models.User.get(user_name=user.user_name)
-    assert user == models.User.get(dn)
+    assert user == backend.get(models.User, user.user_name)
+    assert user == backend.get(models.User, user_name=user.user_name)
+    assert user == backend.get(models.User, dn)
 
     user.delete()
 
diff --git a/tests/backends/test_models.py b/tests/backends/test_models.py
index 0d5c6723..57086a9f 100644
--- a/tests/backends/test_models.py
+++ b/tests/backends/test_models.py
@@ -19,7 +19,7 @@ def test_model_comparison(testclient, backend):
         formatted_name="bar",
     )
     bar.save()
-    foo2 = models.User.get(id=foo1.id)
+    foo2 = backend.get(models.User, id=foo1.id)
 
     assert foo1 == foo2
     assert foo1 != bar
@@ -39,14 +39,14 @@ def test_model_lifecycle(testclient, backend):
     assert not backend.query(models.User)
     assert not backend.query(models.User, id=user.id)
     assert not backend.query(models.User, id="invalid")
-    assert not models.User.get(id=user.id)
+    assert not backend.get(models.User, id=user.id)
 
     user.save()
 
     assert backend.query(models.User) == [user]
     assert backend.query(models.User, id=user.id) == [user]
     assert not backend.query(models.User, id="invalid")
-    assert models.User.get(id=user.id) == user
+    assert backend.get(models.User, id=user.id) == user
 
     user.family_name = "new_family_name"
 
@@ -59,7 +59,7 @@ def test_model_lifecycle(testclient, backend):
     user.delete()
 
     assert not backend.query(models.User, id=user.id)
-    assert not models.User.get(id=user.id)
+    assert not backend.get(models.User, id=user.id)
 
     user.delete()
 
@@ -78,7 +78,7 @@ def test_model_attribute_edition(testclient, backend):
     assert user.family_name == "family_name"
     assert user.emails == ["email1@user.com", "email2@user.com"]
 
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.user_name == "user_name"
     assert user.family_name == "family_name"
     assert user.emails == ["email1@user.com", "email2@user.com"]
@@ -90,7 +90,7 @@ def test_model_attribute_edition(testclient, backend):
     assert user.family_name == "new_family_name"
     assert user.emails == ["email1@user.com"]
 
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.family_name == "new_family_name"
     assert user.emails == ["email1@user.com"]
 
@@ -112,34 +112,34 @@ def test_model_indexation(testclient, backend):
     )
     user.save()
 
-    assert models.User.get(family_name="family_name") == user
-    assert not models.User.get(family_name="new_family_name")
-    assert models.User.get(emails=["email1@user.com"]) == user
-    assert models.User.get(emails=["email2@user.com"]) == user
-    assert not models.User.get(emails=["email3@user.com"])
+    assert backend.get(models.User, family_name="family_name") == user
+    assert not backend.get(models.User, family_name="new_family_name")
+    assert backend.get(models.User, emails=["email1@user.com"]) == user
+    assert backend.get(models.User, emails=["email2@user.com"]) == user
+    assert not backend.get(models.User, emails=["email3@user.com"])
 
     user.family_name = "new_family_name"
     user.emails = ["email2@user.com"]
 
-    assert models.User.get(family_name="family_name") != user
-    assert models.User.get(emails=["email1@user.com"]) != user
-    assert not models.User.get(emails=["email3@user.com"])
+    assert backend.get(models.User, family_name="family_name") != user
+    assert backend.get(models.User, emails=["email1@user.com"]) != user
+    assert not backend.get(models.User, emails=["email3@user.com"])
 
     user.save()
 
-    assert not models.User.get(family_name="family_name")
-    assert models.User.get(family_name="new_family_name") == user
-    assert not models.User.get(emails=["email1@user.com"])
-    assert models.User.get(emails=["email2@user.com"]) == user
-    assert not models.User.get(emails=["email3@user.com"])
+    assert not backend.get(models.User, family_name="family_name")
+    assert backend.get(models.User, family_name="new_family_name") == user
+    assert not backend.get(models.User, emails=["email1@user.com"])
+    assert backend.get(models.User, emails=["email2@user.com"]) == user
+    assert not backend.get(models.User, emails=["email3@user.com"])
 
     user.delete()
 
-    assert not models.User.get(family_name="family_name")
-    assert not models.User.get(family_name="new_family_name")
-    assert not models.User.get(emails=["email1@user.com"])
-    assert not models.User.get(emails=["email2@user.com"])
-    assert not models.User.get(emails=["email3@user.com"])
+    assert not backend.get(models.User, family_name="family_name")
+    assert not backend.get(models.User, family_name="new_family_name")
+    assert not backend.get(models.User, emails=["email1@user.com"])
+    assert not backend.get(models.User, emails=["email2@user.com"])
+    assert not backend.get(models.User, emails=["email3@user.com"])
 
 
 def test_fuzzy_unique_attribute(user, moderator, admin, backend):
diff --git a/tests/core/test_account.py b/tests/core/test_account.py
index ff07c6a1..133d2374 100644
--- a/tests/core/test_account.py
+++ b/tests/core/test_account.py
@@ -78,7 +78,7 @@ def test_admin_self_deletion(testclient, backend):
         .follow(status=200)
     )
 
-    assert models.User.get(user_name="temp") is None
+    assert backend.get(models.User, user_name="temp") is None
 
     with testclient.session_transaction() as sess:
         assert not sess.get("user_id")
@@ -116,7 +116,7 @@ def test_user_self_deletion(testclient, backend):
         .follow(status=200)
     )
 
-    assert models.User.get(user_name="temp") is None
+    assert backend.get(models.User, user_name="temp") is None
 
     with testclient.session_transaction() as sess:
         assert not sess.get("user_id")
@@ -136,7 +136,7 @@ def test_account_locking(user, backend):
     assert user.locked
     user.save()
     assert user.locked
-    assert models.User.get(id=user.id).locked
+    assert backend.get(models.User, id=user.id).locked
     assert backend.check_user_password(user, "correct horse battery staple") == (
         False,
         "Your account has been locked.",
@@ -145,7 +145,7 @@ def test_account_locking(user, backend):
     user.lock_date = None
     user.save()
     assert not user.locked
-    assert not models.User.get(id=user.id).locked
+    assert not backend.get(models.User, id=user.id).locked
     assert backend.check_user_password(user, "correct horse battery staple") == (
         True,
         None,
@@ -165,7 +165,7 @@ def test_account_locking_past_date(user, backend):
     ) - datetime.timedelta(days=30)
     user.save()
     assert user.locked
-    assert models.User.get(id=user.id).locked
+    assert backend.get(models.User, id=user.id).locked
     assert backend.check_user_password(user, "correct horse battery staple") == (
         False,
         "Your account has been locked.",
@@ -185,7 +185,7 @@ def test_account_locking_future_date(user, backend):
     ) + datetime.timedelta(days=365 * 4)
     user.save()
     assert not user.locked
-    assert not models.User.get(id=user.id).locked
+    assert not backend.get(models.User, id=user.id).locked
     assert backend.check_user_password(user, "correct horse battery staple") == (
         True,
         None,
diff --git a/tests/core/test_groups.py b/tests/core/test_groups.py
index f0087d27..bd9d6bb3 100644
--- a/tests/core/test_groups.py
+++ b/tests/core/test_groups.py
@@ -131,12 +131,12 @@ def test_set_groups_with_leading_space_in_user_id_attribute(app, foo_group):
 
 
 def test_moderator_can_create_edit_and_delete_group(
-    testclient, logged_moderator, foo_group
+    testclient, logged_moderator, foo_group, backend
 ):
     # The group does not exist
     res = testclient.get("/groups", status=200)
-    assert models.Group.get(display_name="bar") is None
-    assert models.Group.get(display_name="foo") == foo_group
+    assert backend.get(models.Group, display_name="bar") is None
+    assert backend.get(models.Group, display_name="foo") == foo_group
     res.mustcontain(no="bar")
     res.mustcontain("foo")
 
@@ -150,7 +150,7 @@ def test_moderator_can_create_edit_and_delete_group(
     res = form.submit(status=302).follow(status=200)
 
     logged_moderator.reload()
-    bar_group = models.Group.get(display_name="bar")
+    bar_group = backend.get(models.Group, display_name="bar")
     assert bar_group.display_name == "bar"
     assert bar_group.description == "yolo"
     assert bar_group.members == [
@@ -168,10 +168,10 @@ def test_moderator_can_create_edit_and_delete_group(
     assert res.flashes == [("error", "Group edition failed.")]
     res.mustcontain("This field cannot be edited")
 
-    bar_group = models.Group.get(display_name="bar")
+    bar_group = backend.get(models.Group, display_name="bar")
     assert bar_group.display_name == "bar"
     assert bar_group.description == "yolo"
-    assert models.Group.get(display_name="bar2") is None
+    assert backend.get(models.Group, display_name="bar2") is None
 
     # Group description can be edited
     res = testclient.get("/groups/bar", status=200)
@@ -182,14 +182,14 @@ def test_moderator_can_create_edit_and_delete_group(
     assert res.flashes == [("success", "The group bar has been sucessfully edited.")]
     res = res.follow()
 
-    bar_group = models.Group.get(display_name="bar")
+    bar_group = backend.get(models.Group, display_name="bar")
     assert bar_group.display_name == "bar"
     assert bar_group.description == "yolo2"
 
     # Group is deleted
     res = res.forms["editgroupform"].submit(name="action", value="confirm-delete")
     res = res.form.submit(name="action", value="delete", status=302)
-    assert models.Group.get(display_name="bar") is None
+    assert backend.get(models.Group, display_name="bar") is None
     assert ("success", "The group bar has been sucessfully deleted") in res.flashes
 
 
diff --git a/tests/core/test_invitation.py b/tests/core/test_invitation.py
index 0bc96033..537eb310 100644
--- a/tests/core/test_invitation.py
+++ b/tests/core/test_invitation.py
@@ -7,7 +7,7 @@ from canaille.core.endpoints.account import RegistrationPayload
 
 
 def test_invitation(testclient, logged_admin, foo_group, smtpd, backend):
-    assert models.User.get(user_name="someone") is None
+    assert backend.get(models.User, user_name="someone") is None
 
     res = testclient.get("/invite", status=200)
 
@@ -46,7 +46,7 @@ def test_invitation(testclient, logged_admin, foo_group, smtpd, backend):
     assert ("success", "Your account has been created successfully.") in res.flashes
     res = res.follow(status=200)
 
-    user = models.User.get(user_name="someone")
+    user = backend.get(models.User, user_name="someone")
     foo_group.reload()
     assert backend.check_user_password(user, "whatever")[0]
     assert user.groups == [foo_group]
@@ -62,8 +62,8 @@ def test_invitation(testclient, logged_admin, foo_group, smtpd, backend):
 def test_invitation_editable_user_name(
     testclient, logged_admin, foo_group, smtpd, backend
 ):
-    assert models.User.get(user_name="jackyjack") is None
-    assert models.User.get(user_name="djorje") is None
+    assert backend.get(models.User, user_name="jackyjack") is None
+    assert backend.get(models.User, user_name="djorje") is None
 
     res = testclient.get("/invite", status=200)
 
@@ -102,7 +102,7 @@ def test_invitation_editable_user_name(
     assert ("success", "Your account has been created successfully.") in res.flashes
     res = res.follow(status=200)
 
-    user = models.User.get(user_name="djorje")
+    user = backend.get(models.User, user_name="djorje")
     foo_group.reload()
     assert backend.check_user_password(user, "whatever")[0]
     assert user.groups == [foo_group]
@@ -114,7 +114,7 @@ def test_invitation_editable_user_name(
 
 
 def test_generate_link(testclient, logged_admin, foo_group, smtpd, backend):
-    assert models.User.get(user_name="sometwo") is None
+    assert backend.get(models.User, user_name="sometwo") is None
 
     res = testclient.get("/invite", status=200)
 
@@ -149,7 +149,7 @@ def test_generate_link(testclient, logged_admin, foo_group, smtpd, backend):
     res = res.form.submit(status=302)
     res = res.follow(status=200)
 
-    user = models.User.get(user_name="sometwo")
+    user = backend.get(models.User, user_name="sometwo")
     foo_group.reload()
     assert backend.check_user_password(user, "whatever")[0]
     assert user.groups == [foo_group]
@@ -245,7 +245,7 @@ def test_registration_more_than_48_hours_after_invitation(testclient, foo_group)
     testclient.get(f"/register/{b64}/{hash}", status=302)
 
 
-def test_registration_no_password(testclient, foo_group):
+def test_registration_no_password(testclient, foo_group, backend):
     payload = RegistrationPayload(
         datetime.datetime.now(datetime.timezone.utc).isoformat(),
         "someoneelse",
@@ -264,7 +264,7 @@ def test_registration_no_password(testclient, foo_group):
     res = res.form.submit(status=200)
     res.mustcontain("This field is required.")
 
-    assert not models.User.get(user_name="someoneelse")
+    assert not backend.get(models.User, user_name="someoneelse")
 
     with testclient.session_transaction() as sess:
         assert "user_id" not in sess
@@ -302,7 +302,7 @@ def test_unavailable_if_no_smtp(testclient, logged_admin):
 
 
 def test_groups_are_saved_even_when_user_does_not_have_read_permission(
-    testclient, foo_group
+    testclient, foo_group, backend
 ):
     testclient.app.config["CANAILLE"]["ACL"]["DEFAULT"]["READ"] = [
         "user_name"
@@ -331,7 +331,7 @@ def test_groups_are_saved_even_when_user_does_not_have_read_permission(
     res = res.form.submit(status=302)
     res = res.follow(status=200)
 
-    user = models.User.get(user_name="someoneelse")
+    user = backend.get(models.User, user_name="someoneelse")
     foo_group.reload()
     assert user.groups == [foo_group]
     user.delete()
diff --git a/tests/core/test_profile_creation.py b/tests/core/test_profile_creation.py
index 5bb28f1d..c85ed61a 100644
--- a/tests/core/test_profile_creation.py
+++ b/tests/core/test_profile_creation.py
@@ -6,7 +6,7 @@ def test_user_creation_edition_and_deletion(
 ):
     # The user does not exist.
     res = testclient.get("/users", status=200)
-    assert models.User.get(user_name="george") is None
+    assert backend.get(models.User, user_name="george") is None
     res.mustcontain(no="george")
 
     # Fill the profile for a new user.
@@ -24,7 +24,7 @@ def test_user_creation_edition_and_deletion(
     res = res.form.submit(name="action", value="create-profile", status=302)
     assert ("success", "User account creation succeed.") in res.flashes
     res = res.follow(status=200)
-    george = models.User.get(user_name="george")
+    george = backend.get(models.User, user_name="george")
     foo_group.reload()
     assert "George" == george.given_name
     assert george.groups == [foo_group]
@@ -45,7 +45,7 @@ def test_user_creation_edition_and_deletion(
     res.form["groups"] = [foo_group.id, bar_group.id]
     res = res.form.submit(name="action", value="edit-settings").follow()
 
-    george = models.User.get(user_name="george")
+    george = backend.get(models.User, user_name="george")
     assert "Georgio" == george.given_name
     assert backend.check_user_password(george, "totoyolo")[0]
 
@@ -62,7 +62,7 @@ def test_user_creation_edition_and_deletion(
     res = res.form.submit(name="action", value="confirm-delete", status=200)
     res = res.form.submit(name="action", value="delete", status=302)
     res = res.follow(status=200)
-    assert models.User.get(user_name="george") is None
+    assert backend.get(models.User, user_name="george") is None
     res.mustcontain(no="george")
 
 
@@ -82,7 +82,7 @@ def test_profile_creation_dynamic_validation(testclient, logged_admin, user):
     res.mustcontain("The email 'john@doe.com' is already used")
 
 
-def test_user_creation_without_password(testclient, logged_moderator):
+def test_user_creation_without_password(testclient, logged_moderator, backend):
     res = testclient.get("/profile", status=200)
     res.form["user_name"] = "george"
     res.form["family_name"] = "Abitbol"
@@ -91,7 +91,7 @@ def test_user_creation_without_password(testclient, logged_moderator):
     res = res.form.submit(name="action", value="create-profile", status=302)
     assert ("success", "User account creation succeed.") in res.flashes
     res = res.follow(status=200)
-    george = models.User.get(user_name="george")
+    george = backend.get(models.User, user_name="george")
     assert george.user_name == "george"
     assert not george.has_password()
 
@@ -99,16 +99,16 @@ def test_user_creation_without_password(testclient, logged_moderator):
 
 
 def test_user_creation_form_validation_failed(
-    testclient, logged_moderator, foo_group, bar_group
+    testclient, logged_moderator, foo_group, bar_group, backend
 ):
     res = testclient.get("/users", status=200)
-    assert models.User.get(user_name="george") is None
+    assert backend.get(models.User, user_name="george") is None
     res.mustcontain(no="george")
 
     res = testclient.get("/profile", status=200)
     res = res.form.submit(name="action", value="create-profile")
     assert ("error", "User account creation failed.") in res.flashes
-    assert models.User.get(user_name="george") is None
+    assert backend.get(models.User, user_name="george") is None
 
 
 def test_username_already_taken(
@@ -133,7 +133,7 @@ def test_email_already_taken(testclient, logged_moderator, user, foo_group, bar_
     res.mustcontain("The email 'john@doe.com' is already used")
 
 
-def test_cn_setting_with_given_name_and_surname(testclient, logged_moderator):
+def test_cn_setting_with_given_name_and_surname(testclient, logged_moderator, backend):
     res = testclient.get("/profile", status=200)
     res.form["user_name"] = "george"
     res.form["given_name"] = "George"
@@ -144,12 +144,12 @@ def test_cn_setting_with_given_name_and_surname(testclient, logged_moderator):
         status=200
     )
 
-    george = models.User.get(user_name="george")
+    george = backend.get(models.User, user_name="george")
     assert george.formatted_name == "George Abitbol"
     george.delete()
 
 
-def test_cn_setting_with_surname_only(testclient, logged_moderator):
+def test_cn_setting_with_surname_only(testclient, logged_moderator, backend):
     res = testclient.get("/profile", status=200)
     res.form["user_name"] = "george"
     res.form["family_name"] = "Abitbol"
@@ -159,7 +159,7 @@ def test_cn_setting_with_surname_only(testclient, logged_moderator):
         status=200
     )
 
-    george = models.User.get(user_name="george")
+    george = backend.get(models.User, user_name="george")
     assert george.formatted_name == "Abitbol"
     george.delete()
 
diff --git a/tests/core/test_profile_photo.py b/tests/core/test_profile_photo.py
index bce81091..d173565a 100644
--- a/tests/core/test_profile_photo.py
+++ b/tests/core/test_profile_photo.py
@@ -104,9 +104,9 @@ def test_photo_on_profile_edition(
     assert logged_user.photo is None
 
 
-def test_photo_on_profile_creation(testclient, jpeg_photo, logged_admin):
+def test_photo_on_profile_creation(testclient, jpeg_photo, logged_admin, backend):
     res = testclient.get("/users", status=200)
-    assert models.User.get(user_name="foobar") is None
+    assert backend.get(models.User, user_name="foobar") is None
     res.mustcontain(no="foobar")
 
     res = testclient.get("/profile", status=200)
@@ -119,14 +119,16 @@ def test_photo_on_profile_creation(testclient, jpeg_photo, logged_admin):
         status=200
     )
 
-    user = models.User.get(user_name="foobar")
+    user = backend.get(models.User, user_name="foobar")
     assert user.photo == jpeg_photo
     user.delete()
 
 
-def test_photo_deleted_on_profile_creation(testclient, jpeg_photo, logged_admin):
+def test_photo_deleted_on_profile_creation(
+    testclient, jpeg_photo, logged_admin, backend
+):
     res = testclient.get("/users", status=200)
-    assert models.User.get(user_name="foobar") is None
+    assert backend.get(models.User, user_name="foobar") is None
     res.mustcontain(no="foobar")
 
     res = testclient.get("/profile", status=200)
@@ -140,6 +142,6 @@ def test_photo_deleted_on_profile_creation(testclient, jpeg_photo, logged_admin)
         status=200
     )
 
-    user = models.User.get(user_name="foobar")
+    user = backend.get(models.User, user_name="foobar")
     assert user.photo is None
     user.delete()
diff --git a/tests/core/test_profile_settings.py b/tests/core/test_profile_settings.py
index 462c1e1b..6c159c34 100644
--- a/tests/core/test_profile_settings.py
+++ b/tests/core/test_profile_settings.py
@@ -381,7 +381,7 @@ def test_account_locking(
 
     res = res.form.submit(name="action", value="confirm-lock")
     res = res.form.submit(name="action", value="lock")
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.lock_date <= datetime.datetime.now(datetime.timezone.utc)
     assert user.locked
     res.mustcontain("The account has been locked")
@@ -389,7 +389,7 @@ def test_account_locking(
     res.mustcontain("Unlock")
 
     res = res.form.submit(name="action", value="unlock")
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert not user.lock_date
     assert not user.locked
     res.mustcontain("The account has been unlocked")
@@ -415,7 +415,7 @@ def test_past_lock_date(
     assert res.flashes == [("success", "Profile updated successfully.")]
 
     res = res.follow()
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.lock_date == expiration_datetime
     assert user.locked
 
@@ -438,7 +438,7 @@ def test_future_lock_date(
     assert res.flashes == [("success", "Profile updated successfully.")]
 
     res = res.follow()
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.lock_date == expiration_datetime
     assert not user.locked
     assert res.form["lock_date"].value == expiration_datetime.strftime("%Y-%m-%d %H:%M")
@@ -484,7 +484,7 @@ def test_account_limit_values(
     assert res.flashes == [("success", "Profile updated successfully.")]
 
     res = res.follow()
-    user = models.User.get(id=user.id)
+    user = backend.get(models.User, id=user.id)
     assert user.lock_date == expiration_datetime
     assert not user.locked
 
diff --git a/tests/core/test_registration.py b/tests/core/test_registration.py
index 7d41ef95..b445ca74 100644
--- a/tests/core/test_registration.py
+++ b/tests/core/test_registration.py
@@ -22,7 +22,7 @@ def test_registration_without_email_validation(testclient, backend, foo_group):
     res = res.form.submit()
     assert ("success", "Your account has been created successfully.") in res.flashes
 
-    user = models.User.get(user_name="newuser")
+    user = backend.get(models.User, user_name="newuser")
     assert user
     user.delete()
 
@@ -73,7 +73,7 @@ def test_registration_with_email_validation(testclient, backend, smtpd, foo_grou
         ("success", "Your account has been created successfully."),
     ]
 
-    user = models.User.get(user_name="newuser")
+    user = backend.get(models.User, user_name="newuser")
     assert user
     user.delete()
 
diff --git a/tests/oidc/commands/test_clean.py b/tests/oidc/commands/test_clean.py
index 1dbecae7..69daf252 100644
--- a/tests/oidc/commands/test_clean.py
+++ b/tests/oidc/commands/test_clean.py
@@ -69,8 +69,8 @@ def test_clean_command(testclient, backend, client, user):
     )
     expired_token.save()
 
-    assert models.AuthorizationCode.get(code="my-expired-code")
-    assert models.Token.get(access_token="my-expired-token")
+    assert backend.get(models.AuthorizationCode, code="my-expired-code")
+    assert backend.get(models.Token, access_token="my-expired-token")
     assert expired_code.is_expired()
     assert expired_token.is_expired()
 
@@ -78,5 +78,5 @@ def test_clean_command(testclient, backend, client, user):
     res = runner.invoke(cli, ["clean"])
     assert res.exit_code == 0, res.stdout
 
-    assert models.AuthorizationCode.get() == valid_code
-    assert models.Token.get() == valid_token
+    assert backend.get(models.AuthorizationCode) == valid_code
+    assert backend.get(models.Token) == valid_token
diff --git a/tests/oidc/test_authorization_code_flow.py b/tests/oidc/test_authorization_code_flow.py
index b9d5f45d..9c8d30e5 100644
--- a/tests/oidc/test_authorization_code_flow.py
+++ b/tests/oidc/test_authorization_code_flow.py
@@ -34,7 +34,7 @@ def test_nominal_case(
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
     assert set(authcode.scope) == {
         "openid",
@@ -68,7 +68,7 @@ def test_nominal_case(
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
     assert set(token.scope) == {
@@ -136,7 +136,7 @@ def test_redirect_uri(
     assert res.location.startswith(client.redirect_uris[1])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
     consents = backend.query(models.Consent, client=client, subject=logged_user)
 
@@ -153,7 +153,7 @@ def test_redirect_uri(
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
 
@@ -183,7 +183,7 @@ def test_preconsented_client(
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -202,7 +202,7 @@ def test_preconsented_client(
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
 
@@ -257,7 +257,7 @@ def test_logout_login(testclient, logged_user, client, backend):
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -276,7 +276,7 @@ def test_logout_login(testclient, logged_user, client, backend):
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
 
@@ -341,7 +341,7 @@ def test_code_challenge(testclient, logged_user, client, backend):
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -361,7 +361,7 @@ def test_code_challenge(testclient, logged_user, client, backend):
     )
     access_token = res.json["access_token"]
 
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
 
@@ -398,7 +398,7 @@ def test_consent_already_given(testclient, logged_user, client, backend):
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -456,7 +456,7 @@ def test_when_consent_already_given_but_for_a_smaller_scope(
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -492,7 +492,7 @@ def test_when_consent_already_given_but_for_a_smaller_scope(
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -582,7 +582,7 @@ def test_request_scope_too_large(testclient, logged_user, keypair, client, backe
 
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert set(authcode.scope) == {
         "openid",
         "profile",
@@ -607,7 +607,7 @@ def test_request_scope_too_large(testclient, logged_user, keypair, client, backe
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
     assert set(token.scope) == {
@@ -671,7 +671,7 @@ def test_code_expired(testclient, user, client):
         }
 
 
-def test_code_with_invalid_user(testclient, admin, client):
+def test_code_with_invalid_user(testclient, admin, client, backend):
     user = models.User(
         formatted_name="John Doe",
         family_name="Doe",
@@ -699,7 +699,7 @@ def test_code_with_invalid_user(testclient, admin, client):
     res = res.form.submit(name="answer", value="accept", status=302)
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
 
     user.delete()
 
@@ -721,7 +721,9 @@ def test_code_with_invalid_user(testclient, admin, client):
     authcode.delete()
 
 
-def test_locked_account(testclient, logged_user, client, keypair, trusted_client):
+def test_locked_account(
+    testclient, logged_user, client, keypair, trusted_client, backend
+):
     """Users with a locked account should not be able to exchange code against
     tokens."""
     res = testclient.get(
@@ -743,7 +745,7 @@ def test_locked_account(testclient, logged_user, client, keypair, trusted_client
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     res = testclient.post(
diff --git a/tests/oidc/test_client_admin.py b/tests/oidc/test_client_admin.py
index b5c4a3bd..c42bf219 100644
--- a/tests/oidc/test_client_admin.py
+++ b/tests/oidc/test_client_admin.py
@@ -83,7 +83,7 @@ def test_client_list_search(testclient, logged_admin, client, trusted_client):
     res.mustcontain(no=client.client_name)
 
 
-def test_client_add(testclient, logged_admin):
+def test_client_add(testclient, logged_admin, backend):
     res = testclient.get("/admin/client/add")
     data = {
         "client_name": "foobar",
@@ -112,7 +112,7 @@ def test_client_add(testclient, logged_admin):
     res = res.follow(status=200)
 
     client_id = res.forms["readonly"]["client_id"].value
-    client = models.Client.get(client_id=client_id)
+    client = backend.get(models.Client, client_id=client_id)
 
     assert client.client_name == "foobar"
     assert client.contacts == ["foo@bar.com"]
@@ -214,7 +214,7 @@ def test_client_edit_missing_fields(testclient, client, logged_admin, trusted_cl
     assert client.client_name
 
 
-def test_client_delete(testclient, logged_admin):
+def test_client_delete(testclient, logged_admin, backend):
     client = models.Client(client_id="client_id")
     client.save()
     token = models.Token(
@@ -238,10 +238,10 @@ def test_client_delete(testclient, logged_admin):
     res = res.form.submit(name="action", value="delete")
     res = res.follow()
 
-    assert not models.Client.get()
-    assert not models.Token.get()
-    assert not models.AuthorizationCode.get()
-    assert not models.Consent.get()
+    assert not backend.get(models.Client)
+    assert not backend.get(models.Token)
+    assert not backend.get(models.AuthorizationCode)
+    assert not backend.get(models.Consent)
 
 
 def test_client_delete_invalid_client(testclient, logged_admin, client):
diff --git a/tests/oidc/test_consent.py b/tests/oidc/test_consent.py
index b4547a3a..16787021 100644
--- a/tests/oidc/test_consent.py
+++ b/tests/oidc/test_consent.py
@@ -134,7 +134,7 @@ def test_oidc_authorization_after_revokation(
     )
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user
 
@@ -151,16 +151,16 @@ def test_preconsented_client_appears_in_consent_list(testclient, client, logged_
     res.mustcontain(client.client_name)
 
 
-def test_revoke_preconsented_client(testclient, client, logged_user, token):
+def test_revoke_preconsented_client(testclient, client, logged_user, token, backend):
     client.preconsent = True
     client.save()
-    assert not models.Consent.get()
+    assert not backend.get(models.Consent)
     assert not token.revoked
 
     res = testclient.get(f"/consent/revoke-preconsent/{client.client_id}", status=302)
     assert ("success", "The access has been revoked") in res.flashes
 
-    consent = models.Consent.get()
+    consent = backend.get(models.Consent)
     assert consent.client == client
     assert consent.subject == logged_user
     assert consent.scope == ["openid", "email", "profile", "groups", "address", "phone"]
diff --git a/tests/oidc/test_dynamic_client_registration.py b/tests/oidc/test_dynamic_client_registration.py
index 9e9d336f..5754cb70 100644
--- a/tests/oidc/test_dynamic_client_registration.py
+++ b/tests/oidc/test_dynamic_client_registration.py
@@ -33,7 +33,7 @@ def test_client_registration_with_authentication_static_token(
     headers = {"Authorization": "Bearer static-token"}
 
     res = testclient.post_json("/oauth/register", payload, headers=headers, status=201)
-    client = models.Client.get(client_id=res.json["client_id"])
+    client = backend.get(models.Client, client_id=res.json["client_id"])
 
     assert res.json == {
         "client_id": client.client_id,
@@ -154,7 +154,7 @@ def test_client_registration_with_software_statement(testclient, backend, keypai
     }
     res = testclient.post_json("/oauth/register", payload, status=201)
 
-    client = models.Client.get(client_id=res.json["client_id"])
+    client = backend.get(models.Client, client_id=res.json["client_id"])
     assert res.json == {
         "client_id": client.client_id,
         "client_secret": client.client_secret,
@@ -205,7 +205,7 @@ def test_client_registration_without_authentication_ok(testclient, backend):
 
     res = testclient.post_json("/oauth/register", payload, status=201)
 
-    client = models.Client.get(client_id=res.json["client_id"])
+    client = backend.get(models.Client, client_id=res.json["client_id"])
     assert res.json == {
         "client_id": mock.ANY,
         "client_secret": mock.ANY,
diff --git a/tests/oidc/test_dynamic_client_registration_management.py b/tests/oidc/test_dynamic_client_registration_management.py
index 08594027..3e6bd3f5 100644
--- a/tests/oidc/test_dynamic_client_registration_management.py
+++ b/tests/oidc/test_dynamic_client_registration_management.py
@@ -95,7 +95,7 @@ def test_update(testclient, backend, client, user):
     res = testclient.put_json(
         f"/oauth/register/{client.client_id}", payload, headers=headers, status=200
     )
-    client = models.Client.get(client_id=res.json["client_id"])
+    client = backend.get(models.Client, client_id=res.json["client_id"])
 
     assert res.json == {
         "client_id": client.client_id,
@@ -153,7 +153,7 @@ def test_delete(testclient, backend, user):
         testclient.delete(
             f"/oauth/register/{client.client_id}", headers=headers, status=204
         )
-    assert not models.Client.get(client_id=client.client_id)
+    assert not backend.get(models.Client, client_id=client.client_id)
 
 
 def test_invalid_client(testclient, backend, user):
diff --git a/tests/oidc/test_forms.py b/tests/oidc/test_forms.py
index dae00e7e..a3924e85 100644
--- a/tests/oidc/test_forms.py
+++ b/tests/oidc/test_forms.py
@@ -33,7 +33,7 @@ def test_fieldlist_add(testclient, logged_admin, backend):
     res = res.follow(status=200)
 
     client_id = res.forms["readonly"]["client_id"].value
-    client = models.Client.get(client_id=client_id)
+    client = backend.get(models.Client, client_id=client_id)
 
     assert client.redirect_uris == [
         "https://foo.bar/callback",
@@ -68,7 +68,7 @@ def test_fieldlist_delete(testclient, logged_admin, backend):
     res = res.follow(status=200)
 
     client_id = res.forms["readonly"]["client_id"].value
-    client = models.Client.get(client_id=client_id)
+    client = backend.get(models.Client, client_id=client_id)
 
     assert client.redirect_uris == [
         "https://foo.bar/callback1",
@@ -128,7 +128,7 @@ def test_fieldlist_duplicate_value(testclient, logged_admin, client):
     res.mustcontain("This value is a duplicate")
 
 
-def test_fieldlist_empty_value(testclient, logged_admin):
+def test_fieldlist_empty_value(testclient, logged_admin, backend):
     res = testclient.get("/admin/client/add")
     data = {
         "client_name": "foobar",
@@ -145,7 +145,7 @@ def test_fieldlist_empty_value(testclient, logged_admin):
         status=200, name="fieldlist_add", value="post_logout_redirect_uris-0"
     )
     res.form.submit(status=302, name="action", value="edit")
-    client = models.Client.get()
+    client = backend.get(models.Client)
     client.delete()
 
 
diff --git a/tests/oidc/test_hybrid_flow.py b/tests/oidc/test_hybrid_flow.py
index 92c15762..3f37a24b 100644
--- a/tests/oidc/test_hybrid_flow.py
+++ b/tests/oidc/test_hybrid_flow.py
@@ -32,11 +32,11 @@ def test_oauth_hybrid(testclient, backend, user, client):
     params = parse_qs(urlsplit(res.location).fragment)
 
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     access_token = params["access_token"][0]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     res = testclient.get(
@@ -65,11 +65,11 @@ def test_oidc_hybrid(testclient, backend, logged_user, client, keypair, trusted_
     params = parse_qs(urlsplit(res.location).fragment)
 
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     access_token = params["access_token"][0]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     id_token = params["id_token"][0]
diff --git a/tests/oidc/test_implicit_flow.py b/tests/oidc/test_implicit_flow.py
index 87f125bf..ba1a08ab 100644
--- a/tests/oidc/test_implicit_flow.py
+++ b/tests/oidc/test_implicit_flow.py
@@ -6,7 +6,7 @@ from authlib.jose import jwt
 from canaille.app import models
 
 
-def test_oauth_implicit(testclient, user, client):
+def test_oauth_implicit(testclient, user, client, backend):
     client.grant_types = ["token"]
     client.token_endpoint_auth_method = "none"
 
@@ -37,7 +37,7 @@ def test_oauth_implicit(testclient, user, client):
     params = parse_qs(urlsplit(res.location).fragment)
 
     access_token = params["access_token"][0]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     res = testclient.get(
@@ -51,7 +51,7 @@ def test_oauth_implicit(testclient, user, client):
     client.save()
 
 
-def test_oidc_implicit(testclient, keypair, user, client, trusted_client):
+def test_oidc_implicit(testclient, keypair, user, client, trusted_client, backend):
     client.grant_types = ["token id_token"]
     client.token_endpoint_auth_method = "none"
 
@@ -82,7 +82,7 @@ def test_oidc_implicit(testclient, keypair, user, client, trusted_client):
     params = parse_qs(urlsplit(res.location).fragment)
 
     access_token = params["access_token"][0]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     id_token = params["id_token"][0]
@@ -105,7 +105,7 @@ def test_oidc_implicit(testclient, keypair, user, client, trusted_client):
 
 
 def test_oidc_implicit_with_group(
-    testclient, keypair, user, client, foo_group, trusted_client
+    testclient, keypair, user, client, foo_group, trusted_client, backend
 ):
     client.grant_types = ["token id_token"]
     client.token_endpoint_auth_method = "none"
@@ -137,7 +137,7 @@ def test_oidc_implicit_with_group(
     params = parse_qs(urlsplit(res.location).fragment)
 
     access_token = params["access_token"][0]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     id_token = params["id_token"][0]
diff --git a/tests/oidc/test_password_flow.py b/tests/oidc/test_password_flow.py
index 47c49ca0..daaad5d3 100644
--- a/tests/oidc/test_password_flow.py
+++ b/tests/oidc/test_password_flow.py
@@ -3,7 +3,7 @@ from canaille.app import models
 from . import client_credentials
 
 
-def test_password_flow_basic(testclient, user, client):
+def test_password_flow_basic(testclient, user, client, backend):
     res = testclient.post(
         "/oauth/token",
         params=dict(
@@ -20,7 +20,7 @@ def test_password_flow_basic(testclient, user, client):
     assert res.json["token_type"] == "Bearer"
     access_token = res.json["access_token"]
 
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     res = testclient.get(
@@ -31,7 +31,7 @@ def test_password_flow_basic(testclient, user, client):
     assert res.json["name"] == "John (johnny) Doe"
 
 
-def test_password_flow_post(testclient, user, client):
+def test_password_flow_post(testclient, user, client, backend):
     client.token_endpoint_auth_method = "client_secret_post"
     client.save()
 
@@ -52,7 +52,7 @@ def test_password_flow_post(testclient, user, client):
     assert res.json["token_type"] == "Bearer"
     access_token = res.json["access_token"]
 
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token is not None
 
     res = testclient.get(
diff --git a/tests/oidc/test_refresh_token.py b/tests/oidc/test_refresh_token.py
index 548ecd42..7a99bcd7 100644
--- a/tests/oidc/test_refresh_token.py
+++ b/tests/oidc/test_refresh_token.py
@@ -24,7 +24,7 @@ def test_refresh_token(testclient, logged_user, client, backend):
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     consents = backend.query(models.Consent, client=client, subject=logged_user)
@@ -42,7 +42,7 @@ def test_refresh_token(testclient, logged_user, client, backend):
         status=200,
     )
     access_token = res.json["access_token"]
-    old_token = models.Token.get(access_token=access_token)
+    old_token = backend.get(models.Token, access_token=access_token)
     assert old_token is not None
     assert not old_token.revokation_date
 
@@ -56,7 +56,7 @@ def test_refresh_token(testclient, logged_user, client, backend):
         status=200,
     )
     access_token = res.json["access_token"]
-    new_token = models.Token.get(access_token=access_token)
+    new_token = backend.get(models.Token, access_token=access_token)
     assert new_token is not None
     assert old_token.access_token != new_token.access_token
 
@@ -74,7 +74,7 @@ def test_refresh_token(testclient, logged_user, client, backend):
         consent.delete()
 
 
-def test_refresh_token_with_invalid_user(testclient, client):
+def test_refresh_token_with_invalid_user(testclient, client, backend):
     user = models.User(
         formatted_name="John Doe",
         family_name="Doe",
@@ -103,7 +103,7 @@ def test_refresh_token_with_invalid_user(testclient, client):
 
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    models.AuthorizationCode.get(code=code)
+    backend.get(models.AuthorizationCode, code=code)
 
     res = testclient.post(
         "/oauth/token",
@@ -134,7 +134,7 @@ def test_refresh_token_with_invalid_user(testclient, client):
         "error": "invalid_request",
         "error_description": 'There is no "user" for this token.',
     }
-    models.Token.get(access_token=access_token).delete()
+    backend.get(models.Token, access_token=access_token).delete()
 
 
 def test_cannot_refresh_token_for_locked_users(testclient, logged_user, client):
diff --git a/tests/oidc/test_token_expiration.py b/tests/oidc/test_token_expiration.py
index d4883dcd..dc212ca0 100644
--- a/tests/oidc/test_token_expiration.py
+++ b/tests/oidc/test_token_expiration.py
@@ -26,7 +26,7 @@ def test_token_default_expiration_date(
     res = res.form.submit(name="answer", value="accept", status=302)
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode.lifetime == 84400
 
     res = testclient.post(
@@ -44,7 +44,7 @@ def test_token_default_expiration_date(
     assert res.json["expires_in"] == 864000
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.lifetime == 864000
 
     claims = jwt.decode(access_token, keypair[1])
@@ -86,7 +86,7 @@ def test_token_custom_expiration_date(
     res = res.form.submit(name="answer", value="accept", status=302)
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode.lifetime == 84400
 
     res = testclient.post(
@@ -104,7 +104,7 @@ def test_token_custom_expiration_date(
     assert res.json["expires_in"] == 1000
 
     access_token = res.json["access_token"]
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.lifetime == 1000
 
     claims = jwt.decode(access_token, keypair[1])
diff --git a/tests/oidc/test_token_introspection.py b/tests/oidc/test_token_introspection.py
index c3334a6b..62a4984b 100644
--- a/tests/oidc/test_token_introspection.py
+++ b/tests/oidc/test_token_introspection.py
@@ -58,7 +58,7 @@ def test_token_invalid(testclient, client):
     assert {"active": False} == res.json
 
 
-def test_full_flow(testclient, logged_user, client, user, trusted_client):
+def test_full_flow(testclient, logged_user, client, user, trusted_client, backend):
     res = testclient.get(
         "/oauth/authorize",
         params=dict(
@@ -75,7 +75,7 @@ def test_full_flow(testclient, logged_user, client, user, trusted_client):
     assert res.location.startswith(client.redirect_uris[0])
     params = parse_qs(urlsplit(res.location).query)
     code = params["code"][0]
-    authcode = models.AuthorizationCode.get(code=code)
+    authcode = backend.get(models.AuthorizationCode, code=code)
     assert authcode is not None
 
     res = testclient.post(
@@ -91,7 +91,7 @@ def test_full_flow(testclient, logged_user, client, user, trusted_client):
     )
     access_token = res.json["access_token"]
 
-    token = models.Token.get(access_token=access_token)
+    token = backend.get(models.Token, access_token=access_token)
     assert token.client == client
     assert token.subject == logged_user