diff --git a/changelog.d/10916.misc b/changelog.d/10916.misc
new file mode 100644
index 0000000000..586a0b3a96
--- /dev/null
+++ b/changelog.d/10916.misc
@@ -0,0 +1 @@
+Use direct references to config flags.
diff --git a/synapse/app/_base.py b/synapse/app/_base.py
index 548f6dcde9..749bc1deb9 100644
--- a/synapse/app/_base.py
+++ b/synapse/app/_base.py
@@ -86,11 +86,11 @@ def start_worker_reactor(appname, config, run_command=reactor.run):
 
     start_reactor(
         appname,
-        soft_file_limit=config.soft_file_limit,
-        gc_thresholds=config.gc_thresholds,
+        soft_file_limit=config.server.soft_file_limit,
+        gc_thresholds=config.server.gc_thresholds,
         pid_file=config.worker.worker_pid_file,
         daemonize=config.worker.worker_daemonize,
-        print_pidfile=config.print_pidfile,
+        print_pidfile=config.server.print_pidfile,
         logger=logger,
         run_command=run_command,
     )
@@ -298,7 +298,7 @@ def refresh_certificate(hs):
     Refresh the TLS certificates that Synapse is using by re-reading them from
     disk and updating the TLS context factories to use them.
     """
-    if not hs.config.has_tls_listener():
+    if not hs.config.server.has_tls_listener():
         return
 
     hs.config.read_certificate_from_disk()
diff --git a/synapse/app/admin_cmd.py b/synapse/app/admin_cmd.py
index f2c5b75247..556bcc124e 100644
--- a/synapse/app/admin_cmd.py
+++ b/synapse/app/admin_cmd.py
@@ -195,14 +195,14 @@ def start(config_options):
         config.logging.no_redirect_stdio = True
 
     # Explicitly disable background processes
-    config.update_user_directory = False
+    config.server.update_user_directory = False
     config.worker.run_background_tasks = False
     config.start_pushers = False
     config.pusher_shard_config.instances = []
     config.send_federation = False
     config.federation_shard_config.instances = []
 
-    synapse.events.USE_FROZEN_DICTS = config.use_frozen_dicts
+    synapse.events.USE_FROZEN_DICTS = config.server.use_frozen_dicts
 
     ss = AdminCmdServer(
         config.server.server_name,
diff --git a/synapse/app/generic_worker.py b/synapse/app/generic_worker.py
index 3036e1b4a0..7489f31d9a 100644
--- a/synapse/app/generic_worker.py
+++ b/synapse/app/generic_worker.py
@@ -462,7 +462,7 @@ def start(config_options):
         # For other worker types we force this to off.
         config.server.update_user_directory = False
 
-    synapse.events.USE_FROZEN_DICTS = config.use_frozen_dicts
+    synapse.events.USE_FROZEN_DICTS = config.server.use_frozen_dicts
     synapse.util.caches.TRACK_MEMORY_USAGE = config.caches.track_memory_usage
 
     if config.server.gc_seconds:
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 205831dcda..2b2d4bbf83 100644
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -248,7 +248,7 @@ class SynapseHomeServer(HomeServer):
             resources[SERVER_KEY_V2_PREFIX] = KeyApiV2Resource(self)
 
         if name == "webclient":
-            webclient_loc = self.config.web_client_location
+            webclient_loc = self.config.server.web_client_location
 
             if webclient_loc is None:
                 logger.warning(
@@ -343,7 +343,7 @@ def setup(config_options):
         # generating config files and shouldn't try to continue.
         sys.exit(0)
 
-    events.USE_FROZEN_DICTS = config.use_frozen_dicts
+    events.USE_FROZEN_DICTS = config.server.use_frozen_dicts
     synapse.util.caches.TRACK_MEMORY_USAGE = config.caches.track_memory_usage
 
     if config.server.gc_seconds:
@@ -439,11 +439,11 @@ def run(hs):
 
     _base.start_reactor(
         "synapse-homeserver",
-        soft_file_limit=hs.config.soft_file_limit,
-        gc_thresholds=hs.config.gc_thresholds,
-        pid_file=hs.config.pid_file,
-        daemonize=hs.config.daemonize,
-        print_pidfile=hs.config.print_pidfile,
+        soft_file_limit=hs.config.server.soft_file_limit,
+        gc_thresholds=hs.config.server.gc_thresholds,
+        pid_file=hs.config.server.pid_file,
+        daemonize=hs.config.server.daemonize,
+        print_pidfile=hs.config.server.print_pidfile,
         logger=logger,
     )
 
diff --git a/synapse/app/phone_stats_home.py b/synapse/app/phone_stats_home.py
index 49e7a45e5c..fcd01e833c 100644
--- a/synapse/app/phone_stats_home.py
+++ b/synapse/app/phone_stats_home.py
@@ -74,7 +74,7 @@ async def phone_stats_home(hs, stats, stats_process=_stats_process):
     store = hs.get_datastore()
 
     stats["homeserver"] = hs.config.server.server_name
-    stats["server_context"] = hs.config.server_context
+    stats["server_context"] = hs.config.server.server_context
     stats["timestamp"] = now
     stats["uptime_seconds"] = uptime
     version = sys.version_info
@@ -171,7 +171,7 @@ def start_phone_stats_home(hs):
         current_mau_count_by_service = {}
         reserved_users = ()
         store = hs.get_datastore()
-        if hs.config.limit_usage_by_mau or hs.config.mau_stats_only:
+        if hs.config.server.limit_usage_by_mau or hs.config.server.mau_stats_only:
             current_mau_count = await store.get_monthly_active_count()
             current_mau_count_by_service = (
                 await store.get_monthly_active_count_by_service()
@@ -183,9 +183,9 @@ def start_phone_stats_home(hs):
             current_mau_by_service_gauge.labels(app_service).set(float(count))
 
         registered_reserved_users_mau_gauge.set(float(len(reserved_users)))
-        max_mau_gauge.set(float(hs.config.max_mau_value))
+        max_mau_gauge.set(float(hs.config.server.max_mau_value))
 
-    if hs.config.limit_usage_by_mau or hs.config.mau_stats_only:
+    if hs.config.server.limit_usage_by_mau or hs.config.server.mau_stats_only:
         generate_monthly_active_users()
         clock.looping_call(generate_monthly_active_users, 5 * 60 * 1000)
     # End of monthly active user settings
diff --git a/synapse/config/_base.py b/synapse/config/_base.py
index d974a1a2a8..26152b0924 100644
--- a/synapse/config/_base.py
+++ b/synapse/config/_base.py
@@ -327,7 +327,7 @@ class RootConfig:
         """
         Redirect lookups on this object either to config objects, or values on
         config objects, so that `config.tls.blah` works, as well as legacy uses
-        of things like `config.server_name`. It will first look up the config
+        of things like `config.server.server_name`. It will first look up the config
         section name, and then values on those config classes.
         """
         if item in self._configs.keys():
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 041412d7ad..818b806357 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -1,6 +1,4 @@
-# Copyright 2014-2016 OpenMarket Ltd
-# Copyright 2017-2018 New Vector Ltd
-# Copyright 2019 The Matrix.org Foundation C.I.C.
+# Copyright 2014-2021 The Matrix.org Foundation C.I.C.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
diff --git a/synapse/events/presence_router.py b/synapse/events/presence_router.py
index eb4556cdc1..68b8b19024 100644
--- a/synapse/events/presence_router.py
+++ b/synapse/events/presence_router.py
@@ -45,11 +45,11 @@ def load_legacy_presence_router(hs: "HomeServer"):
     configuration, and registers the hooks they implement.
     """
 
-    if hs.config.presence_router_module_class is None:
+    if hs.config.server.presence_router_module_class is None:
         return
 
-    module = hs.config.presence_router_module_class
-    config = hs.config.presence_router_config
+    module = hs.config.server.presence_router_module_class
+    config = hs.config.server.presence_router_config
     api = hs.get_module_api()
 
     presence_router = module(config=config, module_api=api)
diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index f86113a448..a13fb0148f 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -372,7 +372,7 @@ class EventClientSerializer:
     def __init__(self, hs):
         self.store = hs.get_datastore()
         self.experimental_msc1849_support_enabled = (
-            hs.config.experimental_msc1849_support_enabled
+            hs.config.server.experimental_msc1849_support_enabled
         )
 
     async def serialize_event(
diff --git a/synapse/federation/transport/server/__init__.py b/synapse/federation/transport/server/__init__.py
index 95176ba6f9..c32539bf5a 100644
--- a/synapse/federation/transport/server/__init__.py
+++ b/synapse/federation/transport/server/__init__.py
@@ -117,7 +117,7 @@ class PublicRoomList(BaseFederationServlet):
     ):
         super().__init__(hs, authenticator, ratelimiter, server_name)
         self.handler = hs.get_room_list_handler()
-        self.allow_access = hs.config.allow_public_rooms_over_federation
+        self.allow_access = hs.config.server.allow_public_rooms_over_federation
 
     async def on_GET(
         self, origin: str, content: Literal[None], query: Dict[bytes, List[bytes]]
diff --git a/synapse/handlers/directory.py b/synapse/handlers/directory.py
index 5cfba3c817..9078781d5a 100644
--- a/synapse/handlers/directory.py
+++ b/synapse/handlers/directory.py
@@ -49,7 +49,7 @@ class DirectoryHandler(BaseHandler):
         self.store = hs.get_datastore()
         self.config = hs.config
         self.enable_room_list_search = hs.config.roomdirectory.enable_room_list_search
-        self.require_membership = hs.config.require_membership_for_aliases
+        self.require_membership = hs.config.server.require_membership_for_aliases
         self.third_party_event_rules = hs.get_third_party_event_rules()
 
         self.federation = hs.get_federation_client()
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 16c435ee86..3b0b895b07 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -762,7 +762,7 @@ class FederationHandler(BaseHandler):
         if is_blocked:
             raise SynapseError(403, "This room has been blocked on this server")
 
-        if self.hs.config.block_non_admin_invites:
+        if self.hs.config.server.block_non_admin_invites:
             raise SynapseError(403, "This server does not accept room invites")
 
         if not await self.spam_checker.user_may_invite(
diff --git a/synapse/handlers/identity.py b/synapse/handlers/identity.py
index fe8a995892..a0640fcac0 100644
--- a/synapse/handlers/identity.py
+++ b/synapse/handlers/identity.py
@@ -57,7 +57,7 @@ class IdentityHandler(BaseHandler):
         self.http_client = SimpleHttpClient(hs)
         # An HTTP client for contacting identity servers specified by clients.
         self.blacklisting_http_client = SimpleHttpClient(
-            hs, ip_blacklist=hs.config.federation_ip_range_blacklist
+            hs, ip_blacklist=hs.config.server.federation_ip_range_blacklist
         )
         self.federation_http_client = hs.get_federation_http_client()
         self.hs = hs
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 39c18ecf99..3b8cc50ec0 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -81,7 +81,7 @@ class MessageHandler:
         self.storage = hs.get_storage()
         self.state_store = self.storage.state
         self._event_serializer = hs.get_event_client_serializer()
-        self._ephemeral_events_enabled = hs.config.enable_ephemeral_messages
+        self._ephemeral_events_enabled = hs.config.server.enable_ephemeral_messages
 
         # The scheduled call to self._expire_event. None if no call is currently
         # scheduled.
@@ -415,7 +415,9 @@ class EventCreationHandler:
         self.server_name = hs.hostname
         self.notifier = hs.get_notifier()
         self.config = hs.config
-        self.require_membership_for_aliases = hs.config.require_membership_for_aliases
+        self.require_membership_for_aliases = (
+            hs.config.server.require_membership_for_aliases
+        )
         self._events_shard_config = self.config.worker.events_shard_config
         self._instance_name = hs.get_instance_name()
 
@@ -425,7 +427,7 @@ class EventCreationHandler:
             Membership.JOIN,
             Membership.KNOCK,
         }
-        if self.hs.config.include_profile_data_on_invite:
+        if self.hs.config.server.include_profile_data_on_invite:
             self.membership_types_to_include_profile_data_in.add(Membership.INVITE)
 
         self.send_event = ReplicationSendEventRestServlet.make_client(hs)
@@ -461,11 +463,11 @@ class EventCreationHandler:
         #
         self._rooms_to_exclude_from_dummy_event_insertion: Dict[str, int] = {}
         # The number of forward extremeities before a dummy event is sent.
-        self._dummy_events_threshold = hs.config.dummy_events_threshold
+        self._dummy_events_threshold = hs.config.server.dummy_events_threshold
 
         if (
             self.config.worker.run_background_tasks
-            and self.config.cleanup_extremities_with_dummy_events
+            and self.config.server.cleanup_extremities_with_dummy_events
         ):
             self.clock.looping_call(
                 lambda: run_as_background_process(
@@ -477,7 +479,7 @@ class EventCreationHandler:
 
         self._message_handler = hs.get_message_handler()
 
-        self._ephemeral_events_enabled = hs.config.enable_ephemeral_messages
+        self._ephemeral_events_enabled = hs.config.server.enable_ephemeral_messages
 
         self._external_cache = hs.get_external_cache()
 
diff --git a/synapse/handlers/pagination.py b/synapse/handlers/pagination.py
index a5301ece6f..176e4dfdd4 100644
--- a/synapse/handlers/pagination.py
+++ b/synapse/handlers/pagination.py
@@ -85,12 +85,18 @@ class PaginationHandler:
         self._purges_by_id: Dict[str, PurgeStatus] = {}
         self._event_serializer = hs.get_event_client_serializer()
 
-        self._retention_default_max_lifetime = hs.config.retention_default_max_lifetime
+        self._retention_default_max_lifetime = (
+            hs.config.server.retention_default_max_lifetime
+        )
 
-        self._retention_allowed_lifetime_min = hs.config.retention_allowed_lifetime_min
-        self._retention_allowed_lifetime_max = hs.config.retention_allowed_lifetime_max
+        self._retention_allowed_lifetime_min = (
+            hs.config.server.retention_allowed_lifetime_min
+        )
+        self._retention_allowed_lifetime_max = (
+            hs.config.server.retention_allowed_lifetime_max
+        )
 
-        if hs.config.worker.run_background_tasks and hs.config.retention_enabled:
+        if hs.config.worker.run_background_tasks and hs.config.server.retention_enabled:
             # Run the purge jobs described in the configuration file.
             for job in hs.config.server.retention_purge_jobs:
                 logger.info("Setting up purge job with config: %s", job)
diff --git a/synapse/handlers/profile.py b/synapse/handlers/profile.py
index b23a1541bc..425c0d4973 100644
--- a/synapse/handlers/profile.py
+++ b/synapse/handlers/profile.py
@@ -397,7 +397,7 @@ class ProfileHandler(BaseHandler):
         # when building a membership event. In this case, we must allow the
         # lookup.
         if (
-            not self.hs.config.limit_profile_requests_to_users_who_share_rooms
+            not self.hs.config.server.limit_profile_requests_to_users_who_share_rooms
             or not requester
         ):
             return
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index 4f99f137a2..4a7ccb882e 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -854,7 +854,7 @@ class RegistrationHandler(BaseHandler):
             # Necessary due to auth checks prior to the threepid being
             # written to the db
             if is_threepid_reserved(
-                self.hs.config.mau_limits_reserved_threepids, threepid
+                self.hs.config.server.mau_limits_reserved_threepids, threepid
             ):
                 await self.store.upsert_monthly_active_user(user_id)
 
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index dc4fab2223..bf8a85f563 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -666,7 +666,7 @@ class RoomCreationHandler(BaseHandler):
             await self.ratelimit(requester)
 
         room_version_id = config.get(
-            "room_version", self.config.default_room_version.identifier
+            "room_version", self.config.server.default_room_version.identifier
         )
 
         if not isinstance(room_version_id, str):
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 1a56c82fbd..02103f6c9a 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -90,7 +90,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
         self.third_party_event_rules = hs.get_third_party_event_rules()
         self._server_notices_mxid = self.config.servernotices.server_notices_mxid
         self._enable_lookup = hs.config.enable_3pid_lookup
-        self.allow_per_room_profiles = self.config.allow_per_room_profiles
+        self.allow_per_room_profiles = self.config.server.allow_per_room_profiles
 
         self._join_rate_limiter_local = Ratelimiter(
             store=self.store,
@@ -617,7 +617,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
                 is_requester_admin = await self.auth.is_server_admin(requester.user)
 
             if not is_requester_admin:
-                if self.config.block_non_admin_invites:
+                if self.config.server.block_non_admin_invites:
                     logger.info(
                         "Blocking invite: user is not admin and non-admin "
                         "invites disabled"
@@ -1222,7 +1222,7 @@ class RoomMemberHandler(metaclass=abc.ABCMeta):
         Raises:
             ShadowBanError if the requester has been shadow-banned.
         """
-        if self.config.block_non_admin_invites:
+        if self.config.server.block_non_admin_invites:
             is_requester_admin = await self.auth.is_server_admin(requester.user)
             if not is_requester_admin:
                 raise SynapseError(
@@ -1420,7 +1420,7 @@ class RoomMemberMasterHandler(RoomMemberHandler):
         Returns: bool of whether the complexity is too great, or None
             if unable to be fetched
         """
-        max_complexity = self.hs.config.limit_remote_rooms.complexity
+        max_complexity = self.hs.config.server.limit_remote_rooms.complexity
         complexity = await self.federation_handler.get_room_complexity(
             remote_room_hosts, room_id
         )
@@ -1436,7 +1436,7 @@ class RoomMemberMasterHandler(RoomMemberHandler):
         Args:
             room_id: The room ID to check for complexity.
         """
-        max_complexity = self.hs.config.limit_remote_rooms.complexity
+        max_complexity = self.hs.config.server.limit_remote_rooms.complexity
         complexity = await self.store.get_room_complexity(room_id)
 
         return complexity["v1"] > max_complexity
@@ -1472,7 +1472,7 @@ class RoomMemberMasterHandler(RoomMemberHandler):
             if too_complex is True:
                 raise SynapseError(
                     code=400,
-                    msg=self.hs.config.limit_remote_rooms.complexity_error,
+                    msg=self.hs.config.server.limit_remote_rooms.complexity_error,
                     errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
                 )
 
@@ -1507,7 +1507,7 @@ class RoomMemberMasterHandler(RoomMemberHandler):
             )
             raise SynapseError(
                 code=400,
-                msg=self.hs.config.limit_remote_rooms.complexity_error,
+                msg=self.hs.config.server.limit_remote_rooms.complexity_error,
                 errcode=Codes.RESOURCE_LIMIT_EXCEEDED,
             )
 
diff --git a/synapse/handlers/search.py b/synapse/handlers/search.py
index 8226d6f5a1..6d3333ee00 100644
--- a/synapse/handlers/search.py
+++ b/synapse/handlers/search.py
@@ -105,7 +105,7 @@ class SearchHandler(BaseHandler):
             dict to be returned to the client with results of search
         """
 
-        if not self.hs.config.enable_search:
+        if not self.hs.config.server.enable_search:
             raise SynapseError(400, "Search is disabled on this homeserver")
 
         batch_group = None
diff --git a/synapse/handlers/user_directory.py b/synapse/handlers/user_directory.py
index b91e7cb501..f4430ce3c9 100644
--- a/synapse/handlers/user_directory.py
+++ b/synapse/handlers/user_directory.py
@@ -60,7 +60,7 @@ class UserDirectoryHandler(StateDeltasHandler):
         self.clock = hs.get_clock()
         self.notifier = hs.get_notifier()
         self.is_mine_id = hs.is_mine_id
-        self.update_user_directory = hs.config.update_user_directory
+        self.update_user_directory = hs.config.server.update_user_directory
         self.search_all_users = hs.config.userdirectory.user_directory_search_all_users
         self.spam_checker = hs.get_spam_checker()
         # The current position in the current_state_delta stream
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index cdc36b8d25..4f59224686 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -327,23 +327,23 @@ class MatrixFederationHttpClient:
         self.reactor = hs.get_reactor()
 
         user_agent = hs.version_string
-        if hs.config.user_agent_suffix:
-            user_agent = "%s %s" % (user_agent, hs.config.user_agent_suffix)
+        if hs.config.server.user_agent_suffix:
+            user_agent = "%s %s" % (user_agent, hs.config.server.user_agent_suffix)
         user_agent = user_agent.encode("ascii")
 
         federation_agent = MatrixFederationAgent(
             self.reactor,
             tls_client_options_factory,
             user_agent,
-            hs.config.federation_ip_range_whitelist,
-            hs.config.federation_ip_range_blacklist,
+            hs.config.server.federation_ip_range_whitelist,
+            hs.config.server.federation_ip_range_blacklist,
         )
 
         # Use a BlacklistingAgentWrapper to prevent circumventing the IP
         # blacklist via IP literals in server names
         self.agent = BlacklistingAgentWrapper(
             federation_agent,
-            ip_blacklist=hs.config.federation_ip_range_blacklist,
+            ip_blacklist=hs.config.server.federation_ip_range_blacklist,
         )
 
         self.clock = hs.get_clock()
diff --git a/synapse/replication/tcp/resource.py b/synapse/replication/tcp/resource.py
index 030852cb5b..80f9b23bfd 100644
--- a/synapse/replication/tcp/resource.py
+++ b/synapse/replication/tcp/resource.py
@@ -71,7 +71,7 @@ class ReplicationStreamer:
         self.notifier = hs.get_notifier()
         self._instance_name = hs.get_instance_name()
 
-        self._replication_torture_level = hs.config.replication_torture_level
+        self._replication_torture_level = hs.config.server.replication_torture_level
 
         self.notifier.add_replication_callback(self.on_notifier_poke)
 
diff --git a/synapse/rest/client/account.py b/synapse/rest/client/account.py
index bacb828330..fff133ef10 100644
--- a/synapse/rest/client/account.py
+++ b/synapse/rest/client/account.py
@@ -119,7 +119,7 @@ class EmailPasswordRequestTokenRestServlet(RestServlet):
         )
 
         if existing_user_id is None:
-            if self.config.request_token_inhibit_3pid_errors:
+            if self.config.server.request_token_inhibit_3pid_errors:
                 # Make the client think the operation succeeded. See the rationale in the
                 # comments for request_token_inhibit_3pid_errors.
                 # Also wait for some random amount of time between 100ms and 1s to make it
@@ -403,7 +403,7 @@ class EmailThreepidRequestTokenRestServlet(RestServlet):
         existing_user_id = await self.store.get_user_id_by_threepid("email", email)
 
         if existing_user_id is not None:
-            if self.config.request_token_inhibit_3pid_errors:
+            if self.config.server.request_token_inhibit_3pid_errors:
                 # Make the client think the operation succeeded. See the rationale in the
                 # comments for request_token_inhibit_3pid_errors.
                 # Also wait for some random amount of time between 100ms and 1s to make it
@@ -486,7 +486,7 @@ class MsisdnThreepidRequestTokenRestServlet(RestServlet):
         existing_user_id = await self.store.get_user_id_by_threepid("msisdn", msisdn)
 
         if existing_user_id is not None:
-            if self.hs.config.request_token_inhibit_3pid_errors:
+            if self.hs.config.server.request_token_inhibit_3pid_errors:
                 # Make the client think the operation succeeded. See the rationale in the
                 # comments for request_token_inhibit_3pid_errors.
                 # Also wait for some random amount of time between 100ms and 1s to make it
@@ -857,8 +857,8 @@ def assert_valid_next_link(hs: "HomeServer", next_link: str) -> None:
     # If the domain whitelist is set, the domain must be in it
     if (
         valid
-        and hs.config.next_link_domain_whitelist is not None
-        and next_link_parsed.hostname not in hs.config.next_link_domain_whitelist
+        and hs.config.server.next_link_domain_whitelist is not None
+        and next_link_parsed.hostname not in hs.config.server.next_link_domain_whitelist
     ):
         valid = False
 
diff --git a/synapse/rest/client/capabilities.py b/synapse/rest/client/capabilities.py
index 65b3b5ce2c..d6b6256413 100644
--- a/synapse/rest/client/capabilities.py
+++ b/synapse/rest/client/capabilities.py
@@ -44,10 +44,10 @@ class CapabilitiesRestServlet(RestServlet):
         await self.auth.get_user_by_req(request, allow_guest=True)
         change_password = self.auth_handler.can_change_password()
 
-        response = {
+        response: JsonDict = {
             "capabilities": {
                 "m.room_versions": {
-                    "default": self.config.default_room_version.identifier,
+                    "default": self.config.server.default_room_version.identifier,
                     "available": {
                         v.identifier: v.disposition
                         for v in KNOWN_ROOM_VERSIONS.values()
diff --git a/synapse/rest/client/filter.py b/synapse/rest/client/filter.py
index 6ed60c7418..cc1c2f9731 100644
--- a/synapse/rest/client/filter.py
+++ b/synapse/rest/client/filter.py
@@ -90,7 +90,7 @@ class CreateFilterRestServlet(RestServlet):
             raise AuthError(403, "Can only create filters for local users")
 
         content = parse_json_object_from_request(request)
-        set_timeline_upper_limit(content, self.hs.config.filter_timeline_limit)
+        set_timeline_upper_limit(content, self.hs.config.server.filter_timeline_limit)
 
         filter_id = await self.filtering.add_user_filter(
             user_localpart=target_user.localpart, user_filter=content
diff --git a/synapse/rest/client/profile.py b/synapse/rest/client/profile.py
index d0f20de569..c684636c0a 100644
--- a/synapse/rest/client/profile.py
+++ b/synapse/rest/client/profile.py
@@ -41,7 +41,7 @@ class ProfileDisplaynameRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester_user = None
 
-        if self.hs.config.require_auth_for_profile_requests:
+        if self.hs.config.server.require_auth_for_profile_requests:
             requester = await self.auth.get_user_by_req(request)
             requester_user = requester.user
 
@@ -94,7 +94,7 @@ class ProfileAvatarURLRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester_user = None
 
-        if self.hs.config.require_auth_for_profile_requests:
+        if self.hs.config.server.require_auth_for_profile_requests:
             requester = await self.auth.get_user_by_req(request)
             requester_user = requester.user
 
@@ -146,7 +146,7 @@ class ProfileRestServlet(RestServlet):
     ) -> Tuple[int, JsonDict]:
         requester_user = None
 
-        if self.hs.config.require_auth_for_profile_requests:
+        if self.hs.config.server.require_auth_for_profile_requests:
             requester = await self.auth.get_user_by_req(request)
             requester_user = requester.user
 
diff --git a/synapse/rest/client/register.py b/synapse/rest/client/register.py
index 48b0062cf4..a6eb6f6410 100644
--- a/synapse/rest/client/register.py
+++ b/synapse/rest/client/register.py
@@ -129,7 +129,7 @@ class EmailRegisterRequestTokenRestServlet(RestServlet):
         )
 
         if existing_user_id is not None:
-            if self.hs.config.request_token_inhibit_3pid_errors:
+            if self.hs.config.server.request_token_inhibit_3pid_errors:
                 # Make the client think the operation succeeded. See the rationale in the
                 # comments for request_token_inhibit_3pid_errors.
                 # Also wait for some random amount of time between 100ms and 1s to make it
@@ -209,7 +209,7 @@ class MsisdnRegisterRequestTokenRestServlet(RestServlet):
         )
 
         if existing_user_id is not None:
-            if self.hs.config.request_token_inhibit_3pid_errors:
+            if self.hs.config.server.request_token_inhibit_3pid_errors:
                 # Make the client think the operation succeeded. See the rationale in the
                 # comments for request_token_inhibit_3pid_errors.
                 # Also wait for some random amount of time between 100ms and 1s to make it
@@ -682,7 +682,7 @@ class RegisterRestServlet(RestServlet):
             # written to the db
             if threepid:
                 if is_threepid_reserved(
-                    self.hs.config.mau_limits_reserved_threepids, threepid
+                    self.hs.config.server.mau_limits_reserved_threepids, threepid
                 ):
                     await self.store.upsert_monthly_active_user(registered_user_id)
 
diff --git a/synapse/rest/client/room.py b/synapse/rest/client/room.py
index bf46dc60f2..ed95189b6d 100644
--- a/synapse/rest/client/room.py
+++ b/synapse/rest/client/room.py
@@ -369,7 +369,7 @@ class PublicRoomListRestServlet(TransactionRestServlet):
             # Option to allow servers to require auth when accessing
             # /publicRooms via CS API. This is especially helpful in private
             # federations.
-            if not self.hs.config.allow_public_rooms_without_auth:
+            if not self.hs.config.server.allow_public_rooms_without_auth:
                 raise
 
             # We allow people to not be authed if they're just looking at our
diff --git a/synapse/rest/client/shared_rooms.py b/synapse/rest/client/shared_rooms.py
index 1d90493eb0..09a46737de 100644
--- a/synapse/rest/client/shared_rooms.py
+++ b/synapse/rest/client/shared_rooms.py
@@ -42,7 +42,7 @@ class UserSharedRoomsServlet(RestServlet):
         super().__init__()
         self.auth = hs.get_auth()
         self.store = hs.get_datastore()
-        self.user_directory_active = hs.config.update_user_directory
+        self.user_directory_active = hs.config.server.update_user_directory
 
     async def on_GET(
         self, request: SynapseRequest, user_id: str
diff --git a/synapse/rest/client/sync.py b/synapse/rest/client/sync.py
index 1259058b9b..913216a7c4 100644
--- a/synapse/rest/client/sync.py
+++ b/synapse/rest/client/sync.py
@@ -155,7 +155,7 @@ class SyncRestServlet(RestServlet):
             try:
                 filter_object = json_decoder.decode(filter_id)
                 set_timeline_upper_limit(
-                    filter_object, self.hs.config.filter_timeline_limit
+                    filter_object, self.hs.config.server.filter_timeline_limit
                 )
             except Exception:
                 raise SynapseError(400, "Invalid filter JSON")
diff --git a/synapse/server_notices/resource_limits_server_notices.py b/synapse/server_notices/resource_limits_server_notices.py
index 073b0d754f..8522930b50 100644
--- a/synapse/server_notices/resource_limits_server_notices.py
+++ b/synapse/server_notices/resource_limits_server_notices.py
@@ -47,9 +47,9 @@ class ResourceLimitsServerNotices:
         self._notifier = hs.get_notifier()
 
         self._enabled = (
-            hs.config.limit_usage_by_mau
+            hs.config.server.limit_usage_by_mau
             and self._server_notices_manager.is_enabled()
-            and not hs.config.hs_disabled
+            and not hs.config.server.hs_disabled
         )
 
     async def maybe_send_server_notice_to_user(self, user_id: str) -> None:
@@ -98,7 +98,7 @@ class ResourceLimitsServerNotices:
         try:
             if (
                 limit_type == LimitBlockingTypes.MONTHLY_ACTIVE_USER
-                and not self._config.mau_limit_alerting
+                and not self._config.server.mau_limit_alerting
             ):
                 # We have hit the MAU limit, but MAU alerting is disabled:
                 # reset room if necessary and return
@@ -149,7 +149,7 @@ class ResourceLimitsServerNotices:
             "body": event_body,
             "msgtype": ServerNoticeMsgType,
             "server_notice_type": ServerNoticeLimitReached,
-            "admin_contact": self._config.admin_contact,
+            "admin_contact": self._config.server.admin_contact,
             "limit_type": event_limit_type,
         }
         event = await self._server_notices_manager.send_notice(
diff --git a/synapse/storage/databases/main/censor_events.py b/synapse/storage/databases/main/censor_events.py
index 6305414e3d..eee07227ef 100644
--- a/synapse/storage/databases/main/censor_events.py
+++ b/synapse/storage/databases/main/censor_events.py
@@ -36,7 +36,7 @@ class CensorEventsStore(EventsWorkerStore, CacheInvalidationWorkerStore, SQLBase
 
         if (
             hs.config.worker.run_background_tasks
-            and self.hs.config.redaction_retention_period is not None
+            and self.hs.config.server.redaction_retention_period is not None
         ):
             hs.get_clock().looping_call(self._censor_redactions, 5 * 60 * 1000)
 
@@ -48,7 +48,7 @@ class CensorEventsStore(EventsWorkerStore, CacheInvalidationWorkerStore, SQLBase
         By censor we mean update the event_json table with the redacted event.
         """
 
-        if self.hs.config.redaction_retention_period is None:
+        if self.hs.config.server.redaction_retention_period is None:
             return
 
         if not (
@@ -60,7 +60,9 @@ class CensorEventsStore(EventsWorkerStore, CacheInvalidationWorkerStore, SQLBase
             # created.
             return
 
-        before_ts = self._clock.time_msec() - self.hs.config.redaction_retention_period
+        before_ts = (
+            self._clock.time_msec() - self.hs.config.server.redaction_retention_period
+        )
 
         # We fetch all redactions that:
         #   1. point to an event we have,
diff --git a/synapse/storage/databases/main/client_ips.py b/synapse/storage/databases/main/client_ips.py
index 7e33ae578c..0e1d97aaeb 100644
--- a/synapse/storage/databases/main/client_ips.py
+++ b/synapse/storage/databases/main/client_ips.py
@@ -353,7 +353,7 @@ class ClientIpWorkerStore(ClientIpBackgroundUpdateStore):
     def __init__(self, database: DatabasePool, db_conn, hs):
         super().__init__(database, db_conn, hs)
 
-        self.user_ips_max_age = hs.config.user_ips_max_age
+        self.user_ips_max_age = hs.config.server.user_ips_max_age
 
         if hs.config.worker.run_background_tasks and self.user_ips_max_age:
             self._clock.looping_call(self._prune_old_user_ips, 5 * 1000)
diff --git a/synapse/storage/databases/main/events.py b/synapse/storage/databases/main/events.py
index cc4e31ec30..bc7d213fe2 100644
--- a/synapse/storage/databases/main/events.py
+++ b/synapse/storage/databases/main/events.py
@@ -104,7 +104,7 @@ class PersistEventsStore:
         self._clock = hs.get_clock()
         self._instance_name = hs.get_instance_name()
 
-        self._ephemeral_messages_enabled = hs.config.enable_ephemeral_messages
+        self._ephemeral_messages_enabled = hs.config.server.enable_ephemeral_messages
         self.is_mine_id = hs.is_mine_id
 
         # Ideally we'd move these ID gens here, unfortunately some other ID
diff --git a/synapse/storage/databases/main/monthly_active_users.py b/synapse/storage/databases/main/monthly_active_users.py
index b76ee51a9b..a14ac03d4b 100644
--- a/synapse/storage/databases/main/monthly_active_users.py
+++ b/synapse/storage/databases/main/monthly_active_users.py
@@ -32,8 +32,8 @@ class MonthlyActiveUsersWorkerStore(SQLBaseStore):
         self._clock = hs.get_clock()
         self.hs = hs
 
-        self._limit_usage_by_mau = hs.config.limit_usage_by_mau
-        self._max_mau_value = hs.config.max_mau_value
+        self._limit_usage_by_mau = hs.config.server.limit_usage_by_mau
+        self._max_mau_value = hs.config.server.max_mau_value
 
     @cached(num_args=0)
     async def get_monthly_active_count(self) -> int:
@@ -96,8 +96,8 @@ class MonthlyActiveUsersWorkerStore(SQLBaseStore):
         """
         users = []
 
-        for tp in self.hs.config.mau_limits_reserved_threepids[
-            : self.hs.config.max_mau_value
+        for tp in self.hs.config.server.mau_limits_reserved_threepids[
+            : self.hs.config.server.max_mau_value
         ]:
             user_id = await self.hs.get_datastore().get_user_id_by_threepid(
                 tp["medium"], tp["address"]
@@ -212,7 +212,7 @@ class MonthlyActiveUsersStore(MonthlyActiveUsersWorkerStore):
     def __init__(self, database: DatabasePool, db_conn, hs):
         super().__init__(database, db_conn, hs)
 
-        self._mau_stats_only = hs.config.mau_stats_only
+        self._mau_stats_only = hs.config.server.mau_stats_only
 
         # Do not add more reserved users than the total allowable number
         self.db_pool.new_transaction(
@@ -221,7 +221,7 @@ class MonthlyActiveUsersStore(MonthlyActiveUsersWorkerStore):
             [],
             [],
             self._initialise_reserved_users,
-            hs.config.mau_limits_reserved_threepids[: self._max_mau_value],
+            hs.config.server.mau_limits_reserved_threepids[: self._max_mau_value],
         )
 
     def _initialise_reserved_users(self, txn, threepids):
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index c83089ee63..7279b0924e 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -207,7 +207,7 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
             return False
 
         now = self._clock.time_msec()
-        trial_duration_ms = self.config.mau_trial_days * 24 * 60 * 60 * 1000
+        trial_duration_ms = self.config.server.mau_trial_days * 24 * 60 * 60 * 1000
         is_trial = (now - info["creation_ts"] * 1000) < trial_duration_ms
         return is_trial
 
diff --git a/synapse/storage/databases/main/room.py b/synapse/storage/databases/main/room.py
index 118b390e93..d69eaf80ce 100644
--- a/synapse/storage/databases/main/room.py
+++ b/synapse/storage/databases/main/room.py
@@ -679,8 +679,8 @@ class RoomWorkerStore(SQLBaseStore):
         # policy.
         if not ret:
             return {
-                "min_lifetime": self.config.retention_default_min_lifetime,
-                "max_lifetime": self.config.retention_default_max_lifetime,
+                "min_lifetime": self.config.server.retention_default_min_lifetime,
+                "max_lifetime": self.config.server.retention_default_max_lifetime,
             }
 
         row = ret[0]
@@ -690,10 +690,10 @@ class RoomWorkerStore(SQLBaseStore):
         # The default values will be None if no default policy has been defined, or if one
         # of the attributes is missing from the default policy.
         if row["min_lifetime"] is None:
-            row["min_lifetime"] = self.config.retention_default_min_lifetime
+            row["min_lifetime"] = self.config.server.retention_default_min_lifetime
 
         if row["max_lifetime"] is None:
-            row["max_lifetime"] = self.config.retention_default_max_lifetime
+            row["max_lifetime"] = self.config.server.retention_default_max_lifetime
 
         return row
 
diff --git a/synapse/storage/databases/main/search.py b/synapse/storage/databases/main/search.py
index 2a1e99e17a..c85383c975 100644
--- a/synapse/storage/databases/main/search.py
+++ b/synapse/storage/databases/main/search.py
@@ -51,7 +51,7 @@ class SearchWorkerStore(SQLBaseStore):
             txn:
             entries: entries to be added to the table
         """
-        if not self.hs.config.enable_search:
+        if not self.hs.config.server.enable_search:
             return
         if isinstance(self.database_engine, PostgresEngine):
             sql = (
@@ -105,7 +105,7 @@ class SearchBackgroundUpdateStore(SearchWorkerStore):
     def __init__(self, database: DatabasePool, db_conn, hs):
         super().__init__(database, db_conn, hs)
 
-        if not hs.config.enable_search:
+        if not hs.config.server.enable_search:
             return
 
         self.db_pool.updates.register_background_update_handler(
diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py
index f31880b8ec..a63eaddfdc 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -366,7 +366,7 @@ def _upgrade_existing_database(
             + "new for the server to understand"
         )
 
-    # some of the deltas assume that config.server_name is set correctly, so now
+    # some of the deltas assume that server_name is set correctly, so now
     # is a good time to run the sanity check.
     if not is_empty and "main" in databases:
         from synapse.storage.databases.main import check_database_before_upgrade
diff --git a/tests/api/test_auth.py b/tests/api/test_auth.py
index cccff7af26..3aa9ba3c43 100644
--- a/tests/api/test_auth.py
+++ b/tests/api/test_auth.py
@@ -217,7 +217,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
 
         user_id = "@baldrick:matrix.org"
         macaroon = pymacaroons.Macaroon(
-            location=self.hs.config.server_name,
+            location=self.hs.config.server.server_name,
             identifier="key",
             key=self.hs.config.key.macaroon_secret_key,
         )
@@ -239,7 +239,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
 
         user_id = "@baldrick:matrix.org"
         macaroon = pymacaroons.Macaroon(
-            location=self.hs.config.server_name,
+            location=self.hs.config.server.server_name,
             identifier="key",
             key=self.hs.config.key.macaroon_secret_key,
         )
@@ -268,7 +268,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
         self.store.get_monthly_active_count = simple_async_mock(lots_of_users)
 
         e = self.get_failure(self.auth.check_auth_blocking(), ResourceLimitError)
-        self.assertEquals(e.value.admin_contact, self.hs.config.admin_contact)
+        self.assertEquals(e.value.admin_contact, self.hs.config.server.admin_contact)
         self.assertEquals(e.value.errcode, Codes.RESOURCE_LIMIT_EXCEEDED)
         self.assertEquals(e.value.code, 403)
 
@@ -303,7 +303,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
 
         appservice = ApplicationService(
             "abcd",
-            self.hs.config.server_name,
+            self.hs.config.server.server_name,
             id="1234",
             namespaces={
                 "users": [{"regex": "@_appservice.*:sender", "exclusive": True}]
@@ -332,7 +332,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
 
         appservice = ApplicationService(
             "abcd",
-            self.hs.config.server_name,
+            self.hs.config.server.server_name,
             id="1234",
             namespaces={
                 "users": [{"regex": "@_appservice.*:sender", "exclusive": True}]
@@ -372,7 +372,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
         self.auth_blocking._hs_disabled = True
         self.auth_blocking._hs_disabled_message = "Reason for being disabled"
         e = self.get_failure(self.auth.check_auth_blocking(), ResourceLimitError)
-        self.assertEquals(e.value.admin_contact, self.hs.config.admin_contact)
+        self.assertEquals(e.value.admin_contact, self.hs.config.server.admin_contact)
         self.assertEquals(e.value.errcode, Codes.RESOURCE_LIMIT_EXCEEDED)
         self.assertEquals(e.value.code, 403)
 
@@ -387,7 +387,7 @@ class AuthTestCase(unittest.HomeserverTestCase):
         self.auth_blocking._hs_disabled = True
         self.auth_blocking._hs_disabled_message = "Reason for being disabled"
         e = self.get_failure(self.auth.check_auth_blocking(), ResourceLimitError)
-        self.assertEquals(e.value.admin_contact, self.hs.config.admin_contact)
+        self.assertEquals(e.value.admin_contact, self.hs.config.server.admin_contact)
         self.assertEquals(e.value.errcode, Codes.RESOURCE_LIMIT_EXCEEDED)
         self.assertEquals(e.value.code, 403)
 
diff --git a/tests/federation/test_federation_server.py b/tests/federation/test_federation_server.py
index 0b60cc4261..03e1e11f49 100644
--- a/tests/federation/test_federation_server.py
+++ b/tests/federation/test_federation_server.py
@@ -120,7 +120,7 @@ class StateQueryTests(unittest.FederatingHomeserverTestCase):
 
         self.assertEqual(
             channel.json_body["room_version"],
-            self.hs.config.default_room_version.identifier,
+            self.hs.config.server.default_room_version.identifier,
         )
 
         members = set(
diff --git a/tests/handlers/test_register.py b/tests/handlers/test_register.py
index d3efb67e3e..bd05a2c2d1 100644
--- a/tests/handlers/test_register.py
+++ b/tests/handlers/test_register.py
@@ -175,20 +175,20 @@ class RegistrationTestCase(unittest.HomeserverTestCase):
         self.assertTrue(result_token is not None)
 
     def test_mau_limits_when_disabled(self):
-        self.hs.config.limit_usage_by_mau = False
+        self.hs.config.server.limit_usage_by_mau = False
         # Ensure does not throw exception
         self.get_success(self.get_or_create_user(self.requester, "a", "display_name"))
 
     def test_get_or_create_user_mau_not_blocked(self):
-        self.hs.config.limit_usage_by_mau = True
+        self.hs.config.server.limit_usage_by_mau = True
         self.store.count_monthly_users = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value - 1)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value - 1)
         )
         # Ensure does not throw exception
         self.get_success(self.get_or_create_user(self.requester, "c", "User"))
 
     def test_get_or_create_user_mau_blocked(self):
-        self.hs.config.limit_usage_by_mau = True
+        self.hs.config.server.limit_usage_by_mau = True
         self.store.get_monthly_active_count = Mock(
             return_value=make_awaitable(self.lots_of_users)
         )
@@ -198,7 +198,7 @@ class RegistrationTestCase(unittest.HomeserverTestCase):
         )
 
         self.store.get_monthly_active_count = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value)
         )
         self.get_failure(
             self.get_or_create_user(self.requester, "b", "display_name"),
@@ -206,7 +206,7 @@ class RegistrationTestCase(unittest.HomeserverTestCase):
         )
 
     def test_register_mau_blocked(self):
-        self.hs.config.limit_usage_by_mau = True
+        self.hs.config.server.limit_usage_by_mau = True
         self.store.get_monthly_active_count = Mock(
             return_value=make_awaitable(self.lots_of_users)
         )
@@ -215,7 +215,7 @@ class RegistrationTestCase(unittest.HomeserverTestCase):
         )
 
         self.store.get_monthly_active_count = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value)
         )
         self.get_failure(
             self.handler.register_user(localpart="local_part"), ResourceLimitError
diff --git a/tests/http/test_fedclient.py b/tests/http/test_fedclient.py
index d9a8b077d3..638babae69 100644
--- a/tests/http/test_fedclient.py
+++ b/tests/http/test_fedclient.py
@@ -226,7 +226,7 @@ class FederationClientTests(HomeserverTestCase):
         """Ensure that Synapse does not try to connect to blacklisted IPs"""
 
         # Set up the ip_range blacklist
-        self.hs.config.federation_ip_range_blacklist = IPSet(
+        self.hs.config.server.federation_ip_range_blacklist = IPSet(
             ["127.0.0.0/8", "fe80::/64"]
         )
         self.reactor.lookups["internal"] = "127.0.0.1"
diff --git a/tests/rest/admin/test_user.py b/tests/rest/admin/test_user.py
index ee3ae9cce4..a285d5a7fe 100644
--- a/tests/rest/admin/test_user.py
+++ b/tests/rest/admin/test_user.py
@@ -422,7 +422,7 @@ class UserRegisterTestCase(unittest.HomeserverTestCase):
 
         # Set monthly active users to the limit
         store.get_monthly_active_count = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value)
         )
         # Check that the blocking of monthly active users is working as expected
         # The registration of a new user fails due to the limit
@@ -1485,7 +1485,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
 
         # Set monthly active users to the limit
         self.store.get_monthly_active_count = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value)
         )
         # Check that the blocking of monthly active users is working as expected
         # The registration of a new user fails due to the limit
@@ -1522,7 +1522,7 @@ class UserRestTestCase(unittest.HomeserverTestCase):
 
         # Set monthly active users to the limit
         self.store.get_monthly_active_count = Mock(
-            return_value=make_awaitable(self.hs.config.max_mau_value)
+            return_value=make_awaitable(self.hs.config.server.max_mau_value)
         )
         # Check that the blocking of monthly active users is working as expected
         # The registration of a new user fails due to the limit
diff --git a/tests/rest/client/test_account.py b/tests/rest/client/test_account.py
index 64b0b8458b..2f44547bfb 100644
--- a/tests/rest/client/test_account.py
+++ b/tests/rest/client/test_account.py
@@ -516,7 +516,7 @@ class WhoamiTestCase(unittest.HomeserverTestCase):
 
         appservice = ApplicationService(
             as_token,
-            self.hs.config.server_name,
+            self.hs.config.server.server_name,
             id="1234",
             namespaces={"users": [{"regex": user_id, "exclusive": True}]},
             sender=user_id,
diff --git a/tests/rest/client/test_capabilities.py b/tests/rest/client/test_capabilities.py
index 422361b62a..b9e3602552 100644
--- a/tests/rest/client/test_capabilities.py
+++ b/tests/rest/client/test_capabilities.py
@@ -55,7 +55,7 @@ class CapabilitiesTestCase(unittest.HomeserverTestCase):
             self.assertTrue(room_version in KNOWN_ROOM_VERSIONS, "" + room_version)
 
         self.assertEqual(
-            self.config.default_room_version.identifier,
+            self.config.server.default_room_version.identifier,
             capabilities["m.room_versions"]["default"],
         )
 
diff --git a/tests/rest/client/test_presence.py b/tests/rest/client/test_presence.py
index 1d152352d1..56fe1a3d01 100644
--- a/tests/rest/client/test_presence.py
+++ b/tests/rest/client/test_presence.py
@@ -50,7 +50,7 @@ class PresenceTestCase(unittest.HomeserverTestCase):
         PUT to the status endpoint with use_presence enabled will call
         set_state on the presence handler.
         """
-        self.hs.config.use_presence = True
+        self.hs.config.server.use_presence = True
 
         body = {"presence": "here", "status_msg": "beep boop"}
         channel = self.make_request(
diff --git a/tests/rest/client/test_register.py b/tests/rest/client/test_register.py
index 72a5a11b46..af135d57e1 100644
--- a/tests/rest/client/test_register.py
+++ b/tests/rest/client/test_register.py
@@ -50,7 +50,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         appservice = ApplicationService(
             as_token,
-            self.hs.config.server_name,
+            self.hs.config.server.server_name,
             id="1234",
             namespaces={"users": [{"regex": r"@as_user.*", "exclusive": True}]},
             sender="@as:test",
@@ -74,7 +74,7 @@ class RegisterRestServletTestCase(unittest.HomeserverTestCase):
 
         appservice = ApplicationService(
             as_token,
-            self.hs.config.server_name,
+            self.hs.config.server.server_name,
             id="1234",
             namespaces={"users": [{"regex": r"@as_user.*", "exclusive": True}]},
             sender="@as:test",
diff --git a/tests/server_notices/test_resource_limits_server_notices.py b/tests/server_notices/test_resource_limits_server_notices.py
index 7f25200a5d..36c495954f 100644
--- a/tests/server_notices/test_resource_limits_server_notices.py
+++ b/tests/server_notices/test_resource_limits_server_notices.py
@@ -346,7 +346,7 @@ class TestResourceLimitsServerNoticesWithRealRooms(unittest.HomeserverTestCase):
         invites = []
 
         # Register as many users as the MAU limit allows.
-        for i in range(self.hs.config.max_mau_value):
+        for i in range(self.hs.config.server.max_mau_value):
             localpart = "user%d" % i
             user_id = self.register_user(localpart, "password")
             tok = self.login(localpart, "password")
diff --git a/tests/storage/test_monthly_active_users.py b/tests/storage/test_monthly_active_users.py
index 944dbc34a2..d6b4cdd788 100644
--- a/tests/storage/test_monthly_active_users.py
+++ b/tests/storage/test_monthly_active_users.py
@@ -51,7 +51,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
 
     @override_config({"max_mau_value": 3, "mau_limit_reserved_threepids": gen_3pids(3)})
     def test_initialise_reserved_users(self):
-        threepids = self.hs.config.mau_limits_reserved_threepids
+        threepids = self.hs.config.server.mau_limits_reserved_threepids
 
         # register three users, of which two have reserved 3pids, and a third
         # which is a support user.
@@ -101,9 +101,9 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
         # XXX some of this is redundant. poking things into the config shouldn't
         # work, and in any case it's not obvious what we expect to happen when
         # we advance the reactor.
-        self.hs.config.max_mau_value = 0
+        self.hs.config.server.max_mau_value = 0
         self.reactor.advance(FORTY_DAYS)
-        self.hs.config.max_mau_value = 5
+        self.hs.config.server.max_mau_value = 5
 
         self.get_success(self.store.reap_monthly_active_users())
 
@@ -183,7 +183,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
         self.get_success(d)
 
         count = self.get_success(self.store.get_monthly_active_count())
-        self.assertEqual(count, self.hs.config.max_mau_value)
+        self.assertEqual(count, self.hs.config.server.max_mau_value)
 
         self.reactor.advance(FORTY_DAYS)
 
@@ -199,7 +199,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
     def test_reap_monthly_active_users_reserved_users(self):
         """Tests that reaping correctly handles reaping where reserved users are
         present"""
-        threepids = self.hs.config.mau_limits_reserved_threepids
+        threepids = self.hs.config.server.mau_limits_reserved_threepids
         initial_users = len(threepids)
         reserved_user_number = initial_users - 1
         for i in range(initial_users):
@@ -234,7 +234,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
         self.get_success(d)
 
         count = self.get_success(self.store.get_monthly_active_count())
-        self.assertEqual(count, self.hs.config.max_mau_value)
+        self.assertEqual(count, self.hs.config.server.max_mau_value)
 
     def test_populate_monthly_users_is_guest(self):
         # Test that guest users are not added to mau list
@@ -294,7 +294,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
             {"medium": "email", "address": user2_email},
         ]
 
-        self.hs.config.mau_limits_reserved_threepids = threepids
+        self.hs.config.server.mau_limits_reserved_threepids = threepids
         d = self.store.db_pool.runInteraction(
             "initialise", self.store._initialise_reserved_users, threepids
         )
diff --git a/tests/test_mau.py b/tests/test_mau.py
index 66111eb367..80ab40e255 100644
--- a/tests/test_mau.py
+++ b/tests/test_mau.py
@@ -165,7 +165,7 @@ class TestMauLimit(unittest.HomeserverTestCase):
 
     @override_config({"mau_trial_days": 1})
     def test_trial_users_cant_come_back(self):
-        self.hs.config.mau_trial_days = 1
+        self.hs.config.server.mau_trial_days = 1
 
         # We should be able to register more than the limit initially
         token1 = self.create_user("kermit1")
diff --git a/tests/unittest.py b/tests/unittest.py
index 7a6f5954d0..6d5d87cb78 100644
--- a/tests/unittest.py
+++ b/tests/unittest.py
@@ -232,7 +232,7 @@ class HomeserverTestCase(TestCase):
         # Honour the `use_frozen_dicts` config option. We have to do this
         # manually because this is taken care of in the app `start` code, which
         # we don't run. Plus we want to reset it on tearDown.
-        events.USE_FROZEN_DICTS = self.hs.config.use_frozen_dicts
+        events.USE_FROZEN_DICTS = self.hs.config.server.use_frozen_dicts
 
         if self.hs is None:
             raise Exception("No homeserver returned from make_homeserver.")