diff --git a/swh/docs/django_settings.py b/swh/docs/django_settings.py
--- a/swh/docs/django_settings.py
+++ b/swh/docs/django_settings.py
@@ -1,16 +1,23 @@
-from swh.deposit.settings.development import *  # noqa
-import swh.web.settings.development as web
+# Copyright (C) 2021  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU Affero General Public License version 3, or any later version
+# See top-level LICENSE file for more information
 
-# merge some config variables
-ns = globals()
-for var in dir(web):
-    if var.isupper() and var in ns and isinstance(ns[var], list):
-        for elt in getattr(web, var):
-            if elt not in ns[var]:
-                ns[var].append(elt)
+from importlib import reload
+import os
 
-# swh-web needs to find its static files when running autodoc
-STATIC_DIR = web.STATIC_DIR
-STATICFILES_DIRS = web.STATICFILES_DIRS
 
-SECRET_KEY = "change me"
+def force_django_settings(settings_module):
+    """
+    Enable to modify django settings module dynamically while
+    building sphinx documentation and force settings full reloading.
+    """
+    if os.environ.get("DJANGO_SETTINGS_MODULE") != settings_module:
+        os.environ["DJANGO_SETTINGS_MODULE"] = settings_module
+
+        import django
+        from django import conf as django_conf
+
+        # reset django settings to force their reloading
+        reload(django_conf)
+        django.setup()
diff --git a/swh/docs/sphinx/conf.py b/swh/docs/sphinx/conf.py
--- a/swh/docs/sphinx/conf.py
+++ b/swh/docs/sphinx/conf.py
@@ -5,9 +5,10 @@
 import os
 from typing import Dict
 
-import django
 from sphinx.ext import autodoc
 
+from swh.docs.django_settings import force_django_settings
+
 # General information about the project.
 project = "Software Heritage - Development Documentation"
 copyright = "2015-2021  The Software Heritage developers"
@@ -201,12 +202,24 @@
     anonlabels["routingtable"] = "http-routingtable", ""
 
 
-def setup(app):
-    # hack to set the adequate django settings when building global swh doc
-    # to avoid autodoc build errors
-    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "swh.docs.django_settings")
-    django.setup()
+# sphinx event handler to set adequate django settings prior reading
+# apidoc generated rst files when building doc to avoid autodoc errors
+def set_django_settings(app, env, docname):
+    package_settings = {
+        "auth": "swh.auth.tests.django.app.apptest.settings",
+        "deposit": "swh.deposit.settings.development",
+        "web": "swh.web.settings.development",
+    }
+    for package, settings in package_settings.items():
+        if any(
+            [pattern in docname for pattern in (f"swh.{package}", f"swh-{package}")]
+        ):
+            force_django_settings(settings)
 
+
+def setup(app):
+    # env-purge-doc event is fired before source-read
+    app.connect("env-purge-doc", set_django_settings)
     # add autosimple directive (used in swh-web)
     app.add_autodocumenter(SimpleDocumenter)
     # set an environment variable indicating we are currently building