diff --git a/scripts/synapse_port_db b/scripts/synapse_port_db
index a2a0f364cf..253a6ef6c7 100755
--- a/scripts/synapse_port_db
+++ b/scripts/synapse_port_db
@@ -19,6 +19,7 @@ from twisted.enterprise import adbapi
 
 from synapse.storage._base import LoggingTransaction, SQLBaseStore
 from synapse.storage.engines import create_engine
+from synapse.storage.prepare_database import prepare_database
 
 import argparse
 import curses
@@ -37,6 +38,7 @@ BOOLEAN_COLUMNS = {
     "rooms": ["is_public"],
     "event_edges": ["is_state"],
     "presence_list": ["accepted"],
+    "presence_stream": ["currently_active"],
 }
 
 
@@ -292,7 +294,7 @@ class Porter(object):
             }
         )
 
-        database_engine.prepare_database(db_conn)
+        prepare_database(db_conn, database_engine, config=None)
 
         db_conn.commit()
 
@@ -309,8 +311,8 @@ class Porter(object):
                 **self.postgres_config["args"]
             )
 
-            sqlite_engine = create_engine(FakeConfig(sqlite_config))
-            postgres_engine = create_engine(FakeConfig(postgres_config))
+            sqlite_engine = create_engine(sqlite_config)
+            postgres_engine = create_engine(postgres_config)
 
             self.sqlite_store = Store(sqlite_db_pool, sqlite_engine)
             self.postgres_store = Store(postgres_db_pool, postgres_engine)
@@ -792,8 +794,3 @@ if __name__ == "__main__":
     if end_error_exec_info:
         exc_type, exc_value, exc_traceback = end_error_exec_info
         traceback.print_exception(exc_type, exc_value, exc_traceback)
-
-
-class FakeConfig:
-    def __init__(self, database_config):
-        self.database_config = database_config
diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index fcdc8e6e10..2b4473b9ac 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -33,7 +33,7 @@ from synapse.python_dependencies import (
 from synapse.rest import ClientRestResource
 from synapse.storage.engines import create_engine, IncorrectDatabaseSetup
 from synapse.storage import are_all_users_on_domain
-from synapse.storage.prepare_database import UpgradeDatabaseException
+from synapse.storage.prepare_database import UpgradeDatabaseException, prepare_database
 
 from synapse.server import HomeServer
 
@@ -245,7 +245,7 @@ class SynapseHomeServer(HomeServer):
         except IncorrectDatabaseSetup as e:
             quit_with_error(e.message)
 
-    def get_db_conn(self):
+    def get_db_conn(self, run_new_connection=True):
         # Any param beginning with cp_ is a parameter for adbapi, and should
         # not be passed to the database engine.
         db_params = {
@@ -254,7 +254,8 @@ class SynapseHomeServer(HomeServer):
         }
         db_conn = self.database_engine.module.connect(**db_params)
 
-        self.database_engine.on_new_connection(db_conn)
+        if run_new_connection:
+            self.database_engine.on_new_connection(db_conn)
         return db_conn
 
 
@@ -386,7 +387,7 @@ def setup(config_options):
 
     tls_server_context_factory = context_factory.ServerContextFactory(config)
 
-    database_engine = create_engine(config)
+    database_engine = create_engine(config.database_config)
     config.database_config["args"]["cp_openfun"] = database_engine.on_new_connection
 
     hs = SynapseHomeServer(
@@ -402,8 +403,10 @@ def setup(config_options):
     logger.info("Preparing database: %s...", config.database_config['name'])
 
     try:
-        db_conn = hs.get_db_conn()
-        database_engine.prepare_database(db_conn)
+        db_conn = hs.get_db_conn(run_new_connection=False)
+        prepare_database(db_conn, database_engine, config=config)
+        database_engine.on_new_connection(db_conn)
+
         hs.run_startup_checks(db_conn, database_engine)
 
         db_conn.commit()
diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index 5eeb7042c6..88d8b9ba54 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -37,6 +37,15 @@ VISIBILITY_PRIORITY = (
 )
 
 
+MEMBERSHIP_PRIORITY = (
+    Membership.JOIN,
+    Membership.INVITE,
+    Membership.KNOCK,
+    Membership.LEAVE,
+    Membership.BAN,
+)
+
+
 class BaseHandler(object):
     """
     Common base class for the event handlers.
@@ -72,6 +81,7 @@ class BaseHandler(object):
                 * the user is not currently a member of the room, and:
                 * the user has not been a member of the room since the
                 given events
+            events ([synapse.events.EventBase]): list of events to filter
         """
         forgotten = yield defer.gatherResults([
             self.store.who_forgot_in_room(
@@ -86,6 +96,12 @@ class BaseHandler(object):
         )
 
         def allowed(event, user_id, is_peeking):
+            """
+            Args:
+                event (synapse.events.EventBase): event to check
+                user_id (str)
+                is_peeking (bool)
+            """
             state = event_id_to_state[event.event_id]
 
             # get the room_visibility at the time of the event.
@@ -117,17 +133,30 @@ class BaseHandler(object):
                 if old_priority < new_priority:
                     visibility = prev_visibility
 
-            # get the user's membership at the time of the event. (or rather,
-            # just *after* the event. Which means that people can see their
-            # own join events, but not (currently) their own leave events.)
-            membership_event = state.get((EventTypes.Member, user_id), None)
-            if membership_event:
-                if membership_event.event_id in event_id_forgotten:
-                    membership = None
-                else:
-                    membership = membership_event.membership
-            else:
-                membership = None
+            # likewise, if the event is the user's own membership event, use
+            # the 'most joined' membership
+            membership = None
+            if event.type == EventTypes.Member and event.state_key == user_id:
+                membership = event.content.get("membership", None)
+                if membership not in MEMBERSHIP_PRIORITY:
+                    membership = "leave"
+
+                prev_content = event.unsigned.get("prev_content", {})
+                prev_membership = prev_content.get("membership", None)
+                if prev_membership not in MEMBERSHIP_PRIORITY:
+                    prev_membership = "leave"
+
+                new_priority = MEMBERSHIP_PRIORITY.index(membership)
+                old_priority = MEMBERSHIP_PRIORITY.index(prev_membership)
+                if old_priority < new_priority:
+                    membership = prev_membership
+
+            # otherwise, get the user's membership at the time of the event.
+            if membership is None:
+                membership_event = state.get((EventTypes.Member, user_id), None)
+                if membership_event:
+                    if membership_event.event_id not in event_id_forgotten:
+                        membership = membership_event.membership
 
             # if the user was a member of the room at the time of the event,
             # they can see it.
@@ -204,20 +233,25 @@ class BaseHandler(object):
             )
 
     @defer.inlineCallbacks
-    def _create_new_client_event(self, builder):
-        latest_ret = yield self.store.get_latest_event_ids_and_hashes_in_room(
-            builder.room_id,
-        )
-
-        if latest_ret:
-            depth = max([d for _, _, d in latest_ret]) + 1
+    def _create_new_client_event(self, builder, prev_event_ids=None):
+        if prev_event_ids:
+            prev_events = yield self.store.add_event_hashes(prev_event_ids)
+            prev_max_depth = yield self.store.get_max_depth_of_events(prev_event_ids)
+            depth = prev_max_depth + 1
         else:
-            depth = 1
+            latest_ret = yield self.store.get_latest_event_ids_and_hashes_in_room(
+                builder.room_id,
+            )
 
-        prev_events = [
-            (event_id, prev_hashes)
-            for event_id, prev_hashes, _ in latest_ret
-        ]
+            if latest_ret:
+                depth = max([d for _, _, d in latest_ret]) + 1
+            else:
+                depth = 1
+
+            prev_events = [
+                (event_id, prev_hashes)
+                for event_id, prev_hashes, _ in latest_ret
+            ]
 
         builder.prev_events = prev_events
         builder.depth = depth
@@ -226,49 +260,6 @@ class BaseHandler(object):
 
         context = yield state_handler.compute_event_context(builder)
 
-        # If we've received an invite over federation, there are no latest
-        # events in the room, because we don't know enough about the graph
-        # fragment we received to treat it like a graph, so the above returned
-        # no relevant events. It may have returned some events (if we have
-        # joined and left the room), but not useful ones, like the invite.
-        if (
-            not self.is_host_in_room(context.current_state) and
-            builder.type == EventTypes.Member
-        ):
-            prev_member_event = yield self.store.get_room_member(
-                builder.sender, builder.room_id
-            )
-
-            # The prev_member_event may already be in context.current_state,
-            # despite us not being present in the room; in particular, if
-            # inviting user, and all other local users, have already left.
-            #
-            # In that case, we have all the information we need, and we don't
-            # want to drop "context" - not least because we may need to handle
-            # the invite locally, which will require us to have the whole
-            # context (not just prev_member_event) to auth it.
-            #
-            context_event_ids = (
-                e.event_id for e in context.current_state.values()
-            )
-
-            if (
-                prev_member_event and
-                prev_member_event.event_id not in context_event_ids
-            ):
-                # The prev_member_event is missing from context, so it must
-                # have arrived over federation and is an outlier. We forcibly
-                # set our context to the invite we received over federation
-                builder.prev_events = (
-                    prev_member_event.event_id,
-                    prev_member_event.prev_events
-                )
-
-                context = yield state_handler.compute_event_context(
-                    builder,
-                    old_state=(prev_member_event,)
-                )
-
         if builder.is_state():
             builder.prev_state = yield self.store.add_event_hashes(
                 context.prev_state_events
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index adafd06b24..eb02f0e000 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -284,6 +284,9 @@ class FederationHandler(BaseHandler):
     def backfill(self, dest, room_id, limit, extremities=[]):
         """ Trigger a backfill request to `dest` for the given `room_id`
         """
+        if dest == self.server_name:
+            raise SynapseError(400, "Can't backfill from self.")
+
         if not extremities:
             extremities = yield self.store.get_oldest_events_in_room(room_id)
 
@@ -450,7 +453,7 @@ class FederationHandler(BaseHandler):
 
         likely_domains = [
             domain for domain, depth in curr_domains
-            if domain is not self.server_name
+            if domain != self.server_name
         ]
 
         @defer.inlineCallbacks
@@ -784,13 +787,19 @@ class FederationHandler(BaseHandler):
 
     @defer.inlineCallbacks
     def do_remotely_reject_invite(self, target_hosts, room_id, user_id):
-        origin, event = yield self._make_and_verify_event(
-            target_hosts,
-            room_id,
-            user_id,
-            "leave"
-        )
-        signed_event = self._sign_event(event)
+        try:
+            origin, event = yield self._make_and_verify_event(
+                target_hosts,
+                room_id,
+                user_id,
+                "leave"
+            )
+            signed_event = self._sign_event(event)
+        except SynapseError:
+            raise
+        except CodeMessageException as e:
+            logger.warn("Failed to reject invite: %s", e)
+            raise SynapseError(500, "Failed to reject invite")
 
         # Try the host we successfully got a response to /make_join/
         # request first.
@@ -800,10 +809,16 @@ class FederationHandler(BaseHandler):
         except ValueError:
             pass
 
-        yield self.replication_layer.send_leave(
-            target_hosts,
-            signed_event
-        )
+        try:
+            yield self.replication_layer.send_leave(
+                target_hosts,
+                signed_event
+            )
+        except SynapseError:
+            raise
+        except CodeMessageException as e:
+            logger.warn("Failed to reject invite: %s", e)
+            raise SynapseError(500, "Failed to reject invite")
 
         context = yield self.state_handler.compute_event_context(event)
 
diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py
index 0bb111d047..10608c0dd9 100644
--- a/synapse/handlers/message.py
+++ b/synapse/handlers/message.py
@@ -176,7 +176,7 @@ class MessageHandler(BaseHandler):
         defer.returnValue(chunk)
 
     @defer.inlineCallbacks
-    def create_event(self, event_dict, token_id=None, txn_id=None):
+    def create_event(self, event_dict, token_id=None, txn_id=None, prev_event_ids=None):
         """
         Given a dict from a client, create a new event.
 
@@ -187,6 +187,9 @@ class MessageHandler(BaseHandler):
 
         Args:
             event_dict (dict): An entire event
+            token_id (str)
+            txn_id (str)
+            prev_event_ids (list): The prev event ids to use when creating the event
 
         Returns:
             Tuple of created event (FrozenEvent), Context
@@ -225,6 +228,7 @@ class MessageHandler(BaseHandler):
 
         event, context = yield self._create_new_client_event(
             builder=builder,
+            prev_event_ids=prev_event_ids,
         )
         defer.returnValue((event, context))
 
diff --git a/synapse/handlers/room_member.py b/synapse/handlers/room_member.py
index 01f833c371..b6ef3c91af 100644
--- a/synapse/handlers/room_member.py
+++ b/synapse/handlers/room_member.py
@@ -24,6 +24,7 @@ from synapse.api.constants import (
 )
 from synapse.api.errors import AuthError, SynapseError, Codes
 from synapse.util.logcontext import preserve_context_over_fn
+from synapse.util.async import Linearizer
 
 from signedjson.sign import verify_signed_json
 from signedjson.key import decode_verify_key_bytes
@@ -60,6 +61,8 @@ class RoomMemberHandler(BaseHandler):
     def __init__(self, hs):
         super(RoomMemberHandler, self).__init__(hs)
 
+        self.member_linearizer = Linearizer()
+
         self.clock = hs.get_clock()
 
         self.distributor = hs.get_distributor()
@@ -95,6 +98,82 @@ class RoomMemberHandler(BaseHandler):
                 if remotedomains is not None:
                     remotedomains.add(member.domain)
 
+    @defer.inlineCallbacks
+    def _local_membership_update(
+        self, requester, target, room_id, membership,
+        prev_event_ids,
+        txn_id=None,
+        ratelimit=True,
+    ):
+        msg_handler = self.hs.get_handlers().message_handler
+
+        content = {"membership": membership}
+        if requester.is_guest:
+            content["kind"] = "guest"
+
+        event, context = yield msg_handler.create_event(
+            {
+                "type": EventTypes.Member,
+                "content": content,
+                "room_id": room_id,
+                "sender": requester.user.to_string(),
+                "state_key": target.to_string(),
+
+                # For backwards compatibility:
+                "membership": membership,
+            },
+            token_id=requester.access_token_id,
+            txn_id=txn_id,
+            prev_event_ids=prev_event_ids,
+        )
+
+        yield self.handle_new_client_event(
+            requester,
+            event,
+            context,
+            extra_users=[target],
+            ratelimit=ratelimit,
+        )
+
+        prev_member_event = context.current_state.get(
+            (EventTypes.Member, target.to_string()),
+            None
+        )
+
+        if event.membership == Membership.JOIN:
+            if not prev_member_event or prev_member_event.membership != Membership.JOIN:
+                # Only fire user_joined_room if the user has acutally joined the
+                # room. Don't bother if the user is just changing their profile
+                # info.
+                yield user_joined_room(self.distributor, target, room_id)
+        elif event.membership == Membership.LEAVE:
+            if prev_member_event and prev_member_event.membership == Membership.JOIN:
+                user_left_room(self.distributor, target, room_id)
+
+    @defer.inlineCallbacks
+    def remote_join(self, remote_room_hosts, room_id, user, content):
+        if len(remote_room_hosts) == 0:
+            raise SynapseError(404, "No known servers")
+
+        # We don't do an auth check if we are doing an invite
+        # join dance for now, since we're kinda implicitly checking
+        # that we are allowed to join when we decide whether or not we
+        # need to do the invite/join dance.
+        yield self.hs.get_handlers().federation_handler.do_invite_join(
+            remote_room_hosts,
+            room_id,
+            user.to_string(),
+            content,
+        )
+        yield user_joined_room(self.distributor, user, room_id)
+
+    def reject_remote_invite(self, user_id, room_id, remote_room_hosts):
+        return self.hs.get_handlers().federation_handler.do_remotely_reject_invite(
+            remote_room_hosts,
+            room_id,
+            user_id
+        )
+
     @defer.inlineCallbacks
     def update_membership(
             self,
@@ -106,6 +185,34 @@ class RoomMemberHandler(BaseHandler):
             remote_room_hosts=None,
             third_party_signed=None,
             ratelimit=True,
+    ):
+        key = (target, room_id,)
+
+        with (yield self.member_linearizer.queue(key)):
+            result = yield self._update_membership(
+                requester,
+                target,
+                room_id,
+                action,
+                txn_id=txn_id,
+                remote_room_hosts=remote_room_hosts,
+                third_party_signed=third_party_signed,
+                ratelimit=ratelimit,
+            )
+
+        defer.returnValue(result)
+
+    @defer.inlineCallbacks
+    def _update_membership(
+            self,
+            requester,
+            target,
+            room_id,
+            action,
+            txn_id=None,
+            remote_room_hosts=None,
+            third_party_signed=None,
+            ratelimit=True,
     ):
         effective_membership_state = action
         if action in ["kick", "unban"]:
@@ -120,28 +227,15 @@ class RoomMemberHandler(BaseHandler):
                 third_party_signed,
             )
 
-        msg_handler = self.hs.get_handlers().message_handler
+        if not remote_room_hosts:
+            remote_room_hosts = []
 
-        content = {"membership": effective_membership_state}
-        if requester.is_guest:
-            content["kind"] = "guest"
-
-        event, context = yield msg_handler.create_event(
-            {
-                "type": EventTypes.Member,
-                "content": content,
-                "room_id": room_id,
-                "sender": requester.user.to_string(),
-                "state_key": target.to_string(),
-
-                # For backwards compatibility:
-                "membership": effective_membership_state,
-            },
-            token_id=requester.access_token_id,
-            txn_id=txn_id,
+        latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
+        current_state = yield self.state_handler.get_current_state(
+            room_id, latest_event_ids=latest_event_ids,
         )
 
-        old_state = context.current_state.get((EventTypes.Member, event.state_key))
+        old_state = current_state.get((EventTypes.Member, target.to_string()))
         old_membership = old_state.content.get("membership") if old_state else None
         if action == "unban" and old_membership != "ban":
             raise SynapseError(
@@ -156,13 +250,73 @@ class RoomMemberHandler(BaseHandler):
                 errcode=Codes.BAD_STATE
             )
 
-        member_handler = self.hs.get_handlers().room_member_handler
-        yield member_handler.send_membership_event(
-            requester,
-            event,
-            context,
+        is_host_in_room = self.is_host_in_room(current_state)
+
+        if effective_membership_state == Membership.JOIN:
+            if requester.is_guest and not self._can_guest_join(current_state):
+                # This should be an auth check, but guests are a local concept,
+                # so don't really fit into the general auth process.
+                raise AuthError(403, "Guest access not allowed")
+
+            if not is_host_in_room:
+                inviter = yield self.get_inviter(target.to_string(), room_id)
+                if inviter and not self.hs.is_mine(inviter):
+                    remote_room_hosts.append(inviter.domain)
+
+                content = {"membership": Membership.JOIN}
+
+                profile = self.hs.get_handlers().profile_handler
+                content["displayname"] = yield profile.get_displayname(target)
+                content["avatar_url"] = yield profile.get_avatar_url(target)
+
+                if requester.is_guest:
+                    content["kind"] = "guest"
+
+                ret = yield self.remote_join(
+                    remote_room_hosts, room_id, target, content
+                )
+                defer.returnValue(ret)
+
+        elif effective_membership_state == Membership.LEAVE:
+            if not is_host_in_room:
+                # perhaps we've been invited
+                inviter = yield self.get_inviter(target.to_string(), room_id)
+                if not inviter:
+                    raise SynapseError(404, "Not a known room")
+
+                if self.hs.is_mine(inviter):
+                    # the inviter was on our server, but has now left. Carry on
+                    # with the normal rejection codepath.
+                    #
+                    # This is a bit of a hack, because the room might still be
+                    # active on other servers.
+                    pass
+                else:
+                    # send the rejection to the inviter's HS.
+                    remote_room_hosts = remote_room_hosts + [inviter.domain]
+
+                    try:
+                        ret = yield self.reject_remote_invite(
+                            target.to_string(), room_id, remote_room_hosts
+                        )
+                        defer.returnValue(ret)
+                    except SynapseError as e:
+                        logger.warn("Failed to reject invite: %s", e)
+
+                        yield self.store.locally_reject_invite(
+                            target.to_string(), room_id
+                        )
+
+                        defer.returnValue({})
+
+        yield self._local_membership_update(
+            requester=requester,
+            target=target,
+            room_id=room_id,
+            membership=effective_membership_state,
+            txn_id=txn_id,
             ratelimit=ratelimit,
-            remote_room_hosts=remote_room_hosts,
+            prev_event_ids=latest_event_ids,
         )
 
     @defer.inlineCallbacks
@@ -211,73 +365,19 @@ class RoomMemberHandler(BaseHandler):
         if prev_event is not None:
             return
 
-        action = "send"
-
         if event.membership == Membership.JOIN:
             if requester.is_guest and not self._can_guest_join(context.current_state):
                 # This should be an auth check, but guests are a local concept,
                 # so don't really fit into the general auth process.
                 raise AuthError(403, "Guest access not allowed")
-            do_remote_join_dance, remote_room_hosts = self._should_do_dance(
-                context,
-                (self.get_inviter(event.state_key, context.current_state)),
-                remote_room_hosts,
-            )
-            if do_remote_join_dance:
-                action = "remote_join"
-        elif event.membership == Membership.LEAVE:
-            is_host_in_room = self.is_host_in_room(context.current_state)
 
-            if not is_host_in_room:
-                # perhaps we've been invited
-                inviter = self.get_inviter(
-                    target_user.to_string(), context.current_state
-                )
-                if not inviter:
-                    raise SynapseError(404, "Not a known room")
-
-                if self.hs.is_mine(inviter):
-                    # the inviter was on our server, but has now left. Carry on
-                    # with the normal rejection codepath.
-                    #
-                    # This is a bit of a hack, because the room might still be
-                    # active on other servers.
-                    pass
-                else:
-                    # send the rejection to the inviter's HS.
-                    remote_room_hosts = remote_room_hosts + [inviter.domain]
-                    action = "remote_reject"
-
-        federation_handler = self.hs.get_handlers().federation_handler
-
-        if action == "remote_join":
-            if len(remote_room_hosts) == 0:
-                raise SynapseError(404, "No known servers")
-
-            # We don't do an auth check if we are doing an invite
-            # join dance for now, since we're kinda implicitly checking
-            # that we are allowed to join when we decide whether or not we
-            # need to do the invite/join dance.
-            yield federation_handler.do_invite_join(
-                remote_room_hosts,
-                event.room_id,
-                event.user_id,
-                event.content,
-            )
-        elif action == "remote_reject":
-            yield federation_handler.do_remotely_reject_invite(
-                remote_room_hosts,
-                room_id,
-                event.user_id
-            )
-        else:
-            yield self.handle_new_client_event(
-                requester,
-                event,
-                context,
-                extra_users=[target_user],
-                ratelimit=ratelimit,
-            )
+        yield self.handle_new_client_event(
+            requester,
+            event,
+            context,
+            extra_users=[target_user],
+            ratelimit=ratelimit,
+        )
 
         prev_member_event = context.current_state.get(
             (EventTypes.Member, target_user.to_string()),
@@ -306,11 +406,11 @@ class RoomMemberHandler(BaseHandler):
             and guest_access.content["guest_access"] == "can_join"
         )
 
-    def _should_do_dance(self, context, inviter, room_hosts=None):
+    def _should_do_dance(self, current_state, inviter, room_hosts=None):
         # TODO: Shouldn't this be remote_room_host?
         room_hosts = room_hosts or []
 
-        is_host_in_room = self.is_host_in_room(context.current_state)
+        is_host_in_room = self.is_host_in_room(current_state)
         if is_host_in_room:
             return False, room_hosts
 
@@ -344,11 +444,14 @@ class RoomMemberHandler(BaseHandler):
 
         defer.returnValue((RoomID.from_string(room_id), servers))
 
-    def get_inviter(self, user_id, current_state):
-        prev_state = current_state.get((EventTypes.Member, user_id))
-        if prev_state and prev_state.membership == Membership.INVITE:
-            return UserID.from_string(prev_state.user_id)
-        return None
+    @defer.inlineCallbacks
+    def get_inviter(self, user_id, room_id):
+        invite = yield self.store.get_invite_for_user_in_room(
+            user_id=user_id,
+            room_id=room_id,
+        )
+        if invite:
+            defer.returnValue(UserID.from_string(invite.sender))
 
     @defer.inlineCallbacks
     def get_joined_rooms_for_user(self, user):
diff --git a/synapse/replication/resource.py b/synapse/replication/resource.py
index c51a6fa103..a543af68f8 100644
--- a/synapse/replication/resource.py
+++ b/synapse/replication/resource.py
@@ -145,32 +145,43 @@ class ReplicationResource(Resource):
         timeout = parse_integer(request, "timeout", 10 * 1000)
 
         request.setHeader(b"Content-Type", b"application/json")
-        writer = _Writer(request)
 
-        @defer.inlineCallbacks
+        request_streams = {
+            name: parse_integer(request, name)
+            for names in STREAM_NAMES for name in names
+        }
+        request_streams["streams"] = parse_string(request, "streams")
+
         def replicate():
-            current_token = yield self.current_replication_token()
-            logger.info("Replicating up to %r", current_token)
+            return self.replicate(request_streams, limit)
 
-            yield self.account_data(writer, current_token, limit)
-            yield self.events(writer, current_token, limit)
-            yield self.presence(writer, current_token)  # TODO: implement limit
-            yield self.typing(writer, current_token)  # TODO: implement limit
-            yield self.receipts(writer, current_token, limit)
-            yield self.push_rules(writer, current_token, limit)
-            yield self.pushers(writer, current_token, limit)
-            yield self.state(writer, current_token, limit)
-            self.streams(writer, current_token)
+        result = yield self.notifier.wait_for_replication(replicate, timeout)
 
-            logger.info("Replicated %d rows", writer.total)
-            defer.returnValue(writer.total)
+        request.write(json.dumps(result, ensure_ascii=False))
+        finish_request(request)
 
-        yield self.notifier.wait_for_replication(replicate, timeout)
+    @defer.inlineCallbacks
+    def replicate(self, request_streams, limit):
+        writer = _Writer()
+        current_token = yield self.current_replication_token()
+        logger.info("Replicating up to %r", current_token)
 
-        writer.finish()
+        yield self.account_data(writer, current_token, limit, request_streams)
+        yield self.events(writer, current_token, limit, request_streams)
+        # TODO: implement limit
+        yield self.presence(writer, current_token, request_streams)
+        yield self.typing(writer, current_token, request_streams)
+        yield self.receipts(writer, current_token, limit, request_streams)
+        yield self.push_rules(writer, current_token, limit, request_streams)
+        yield self.pushers(writer, current_token, limit, request_streams)
+        yield self.state(writer, current_token, limit, request_streams)
+        self.streams(writer, current_token, request_streams)
 
-    def streams(self, writer, current_token):
-        request_token = parse_string(writer.request, "streams")
+        logger.info("Replicated %d rows", writer.total)
+        defer.returnValue(writer.finish())
+
+    def streams(self, writer, current_token, request_streams):
+        request_token = request_streams.get("streams")
 
         streams = []
 
@@ -195,9 +206,9 @@ class ReplicationResource(Resource):
                 )
 
     @defer.inlineCallbacks
-    def events(self, writer, current_token, limit):
-        request_events = parse_integer(writer.request, "events")
-        request_backfill = parse_integer(writer.request, "backfill")
+    def events(self, writer, current_token, limit, request_streams):
+        request_events = request_streams.get("events")
+        request_backfill = request_streams.get("backfill")
 
         if request_events is not None or request_backfill is not None:
             if request_events is None:
@@ -228,10 +239,10 @@ class ReplicationResource(Resource):
             )
 
     @defer.inlineCallbacks
-    def presence(self, writer, current_token):
+    def presence(self, writer, current_token, request_streams):
         current_position = current_token.presence
 
-        request_presence = parse_integer(writer.request, "presence")
+        request_presence = request_streams.get("presence")
 
         if request_presence is not None:
             presence_rows = yield self.presence_handler.get_all_presence_updates(
@@ -244,10 +255,10 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def typing(self, writer, current_token):
+    def typing(self, writer, current_token, request_streams):
         current_position = current_token.presence
 
-        request_typing = parse_integer(writer.request, "typing")
+        request_typing = request_streams.get("typing")
 
         if request_typing is not None:
             typing_rows = yield self.typing_handler.get_all_typing_updates(
@@ -258,10 +269,10 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def receipts(self, writer, current_token, limit):
+    def receipts(self, writer, current_token, limit, request_streams):
         current_position = current_token.receipts
 
-        request_receipts = parse_integer(writer.request, "receipts")
+        request_receipts = request_streams.get("receipts")
 
         if request_receipts is not None:
             receipts_rows = yield self.store.get_all_updated_receipts(
@@ -272,12 +283,12 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def account_data(self, writer, current_token, limit):
+    def account_data(self, writer, current_token, limit, request_streams):
         current_position = current_token.account_data
 
-        user_account_data = parse_integer(writer.request, "user_account_data")
-        room_account_data = parse_integer(writer.request, "room_account_data")
-        tag_account_data = parse_integer(writer.request, "tag_account_data")
+        user_account_data = request_streams.get("user_account_data")
+        room_account_data = request_streams.get("room_account_data")
+        tag_account_data = request_streams.get("tag_account_data")
 
         if user_account_data is not None or room_account_data is not None:
             if user_account_data is None:
@@ -303,10 +314,10 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def push_rules(self, writer, current_token, limit):
+    def push_rules(self, writer, current_token, limit, request_streams):
         current_position = current_token.push_rules
 
-        push_rules = parse_integer(writer.request, "push_rules")
+        push_rules = request_streams.get("push_rules")
 
         if push_rules is not None:
             rows = yield self.store.get_all_push_rule_updates(
@@ -318,10 +329,11 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def pushers(self, writer, current_token, limit):
+    def pushers(self, writer, current_token, limit, request_streams):
         current_position = current_token.pushers
 
-        pushers = parse_integer(writer.request, "pushers")
+        pushers = request_streams.get("pushers")
+
         if pushers is not None:
             updated, deleted = yield self.store.get_all_updated_pushers(
                 pushers, current_position, limit
@@ -336,10 +348,11 @@ class ReplicationResource(Resource):
             ))
 
     @defer.inlineCallbacks
-    def state(self, writer, current_token, limit):
+    def state(self, writer, current_token, limit, request_streams):
         current_position = current_token.state
 
-        state = parse_integer(writer.request, "state")
+        state = request_streams.get("state")
+
         if state is not None:
             state_groups, state_group_state = (
                 yield self.store.get_all_new_state_groups(
@@ -356,9 +369,8 @@ class ReplicationResource(Resource):
 
 class _Writer(object):
     """Writes the streams as a JSON object as the response to the request"""
-    def __init__(self, request):
+    def __init__(self):
         self.streams = {}
-        self.request = request
         self.total = 0
 
     def write_header_and_rows(self, name, rows, fields, position=None):
@@ -377,8 +389,7 @@ class _Writer(object):
         self.total += len(rows)
 
     def finish(self):
-        self.request.write(json.dumps(self.streams, ensure_ascii=False))
-        finish_request(self.request)
+        return self.streams
 
 
 class _ReplicationToken(collections.namedtuple("_ReplicationToken", (
diff --git a/synapse/replication/slave/__init__.py b/synapse/replication/slave/__init__.py
new file mode 100644
index 0000000000..b7df13c9ee
--- /dev/null
+++ b/synapse/replication/slave/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/synapse/replication/slave/storage/__init__.py b/synapse/replication/slave/storage/__init__.py
new file mode 100644
index 0000000000..b7df13c9ee
--- /dev/null
+++ b/synapse/replication/slave/storage/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/synapse/replication/slave/storage/_base.py b/synapse/replication/slave/storage/_base.py
new file mode 100644
index 0000000000..46e43ce1c7
--- /dev/null
+++ b/synapse/replication/slave/storage/_base.py
@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from synapse.storage._base import SQLBaseStore
+from twisted.internet import defer
+
+
+class BaseSlavedStore(SQLBaseStore):
+    def __init__(self, db_conn, hs):
+        super(BaseSlavedStore, self).__init__(hs)
+
+    def stream_positions(self):
+        return {}
+
+    def process_replication(self, result):
+        return defer.succeed(None)
diff --git a/synapse/replication/slave/storage/_slaved_id_tracker.py b/synapse/replication/slave/storage/_slaved_id_tracker.py
new file mode 100644
index 0000000000..24b5c79d4a
--- /dev/null
+++ b/synapse/replication/slave/storage/_slaved_id_tracker.py
@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from synapse.storage.util.id_generators import _load_current_id
+
+
+class SlavedIdTracker(object):
+    def __init__(self, db_conn, table, column, extra_tables=[], step=1):
+        self.step = step
+        self._current = _load_current_id(db_conn, table, column, step)
+        for table, column in extra_tables:
+            self.advance(_load_current_id(db_conn, table, column))
+
+    def advance(self, new_id):
+        self._current = (max if self.step > 0 else min)(self._current, new_id)
+
+    def get_current_token(self):
+        return self._current
diff --git a/synapse/replication/slave/storage/events.py b/synapse/replication/slave/storage/events.py
new file mode 100644
index 0000000000..707ddd248a
--- /dev/null
+++ b/synapse/replication/slave/storage/events.py
@@ -0,0 +1,204 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+from ._base import BaseSlavedStore
+from ._slaved_id_tracker import SlavedIdTracker
+
+from synapse.api.constants import EventTypes
+from synapse.events import FrozenEvent
+from synapse.storage import DataStore
+from synapse.storage.room import RoomStore
+from synapse.storage.roommember import RoomMemberStore
+from synapse.storage.event_federation import EventFederationStore
+from synapse.storage.state import StateStore
+from synapse.util.caches.stream_change_cache import StreamChangeCache
+
+import ujson as json
+
+# So, um, we want to borrow a load of functions intended for reading from
+# a DataStore, but we don't want to take functions that either write to the
+# DataStore or are cached and don't have cache invalidation logic.
+#
+# Rather than write duplicate versions of those functions, or lift them to
+# a common base class, we going to grab the underlying __func__ object from
+# the method descriptor on the DataStore and chuck them into our class.
+
+
+class SlavedEventStore(BaseSlavedStore):
+
+    def __init__(self, db_conn, hs):
+        super(SlavedEventStore, self).__init__(db_conn, hs)
+        self._stream_id_gen = SlavedIdTracker(
+            db_conn, "events", "stream_ordering",
+        )
+        self._backfill_id_gen = SlavedIdTracker(
+            db_conn, "events", "stream_ordering", step=-1
+        )
+        events_max = self._stream_id_gen.get_current_token()
+        event_cache_prefill, min_event_val = self._get_cache_dict(
+            db_conn, "events",
+            entity_column="room_id",
+            stream_column="stream_ordering",
+            max_value=events_max,
+        )
+        self._events_stream_cache = StreamChangeCache(
+            "EventsRoomStreamChangeCache", min_event_val,
+            prefilled_cache=event_cache_prefill,
+        )
+
+    # Cached functions can't be accessed through a class instance so we need
+    # to reach inside the __dict__ to extract them.
+    get_room_name_and_aliases = RoomStore.__dict__["get_room_name_and_aliases"]
+    get_rooms_for_user = RoomMemberStore.__dict__["get_rooms_for_user"]
+    get_users_in_room = RoomMemberStore.__dict__["get_users_in_room"]
+    get_latest_event_ids_in_room = EventFederationStore.__dict__[
+        "get_latest_event_ids_in_room"
+    ]
+    _get_current_state_for_key = StateStore.__dict__[
+        "_get_current_state_for_key"
+    ]
+
+    get_current_state = DataStore.get_current_state.__func__
+    get_current_state_for_key = DataStore.get_current_state_for_key.__func__
+    get_rooms_for_user_where_membership_is = (
+        DataStore.get_rooms_for_user_where_membership_is.__func__
+    )
+    get_membership_changes_for_user = (
+        DataStore.get_membership_changes_for_user.__func__
+    )
+    get_room_events_max_id = DataStore.get_room_events_max_id.__func__
+    get_room_events_stream_for_room = (
+        DataStore.get_room_events_stream_for_room.__func__
+    )
+    _set_before_and_after = DataStore._set_before_and_after
+
+    _get_events = DataStore._get_events.__func__
+    _get_events_from_cache = DataStore._get_events_from_cache.__func__
+
+    _invalidate_get_event_cache = DataStore._invalidate_get_event_cache.__func__
+    _parse_events_txn = DataStore._parse_events_txn.__func__
+    _get_events_txn = DataStore._get_events_txn.__func__
+    _enqueue_events = DataStore._enqueue_events.__func__
+    _do_fetch = DataStore._do_fetch.__func__
+    _fetch_events_txn = DataStore._fetch_events_txn.__func__
+    _fetch_event_rows = DataStore._fetch_event_rows.__func__
+    _get_event_from_row = DataStore._get_event_from_row.__func__
+    _get_event_from_row_txn = DataStore._get_event_from_row_txn.__func__
+    _get_rooms_for_user_where_membership_is_txn = (
+        DataStore._get_rooms_for_user_where_membership_is_txn.__func__
+    )
+    _get_members_rows_txn = DataStore._get_members_rows_txn.__func__
+
+    def stream_positions(self):
+        result = super(SlavedEventStore, self).stream_positions()
+        result["events"] = self._stream_id_gen.get_current_token()
+        result["backfilled"] = self._backfill_id_gen.get_current_token()
+        return result
+
+    def process_replication(self, result):
+        state_resets = set(
+            r[0] for r in result.get("state_resets", {"rows": []})["rows"]
+        )
+
+        stream = result.get("events")
+        if stream:
+            self._stream_id_gen.advance(stream["position"])
+            for row in stream["rows"]:
+                self._process_replication_row(
+                    row, backfilled=False, state_resets=state_resets
+                )
+
+        stream = result.get("backfill")
+        if stream:
+            self._backfill_id_gen.advance(stream["position"])
+            for row in stream["rows"]:
+                self._process_replication_row(
+                    row, backfilled=True, state_resets=state_resets
+                )
+
+        stream = result.get("forward_ex_outliers")
+        if stream:
+            for row in stream["rows"]:
+                event_id = row[1]
+                self._invalidate_get_event_cache(event_id)
+
+        stream = result.get("backward_ex_outliers")
+        if stream:
+            for row in stream["rows"]:
+                event_id = row[1]
+                self._invalidate_get_event_cache(event_id)
+
+        return super(SlavedEventStore, self).process_replication(result)
+
+    def _process_replication_row(self, row, backfilled, state_resets):
+        position = row[0]
+        internal = json.loads(row[1])
+        event_json = json.loads(row[2])
+
+        event = FrozenEvent(event_json, internal_metadata_dict=internal)
+        self._invalidate_caches_for_event(
+            event, backfilled, reset_state=position in state_resets
+        )
+
+    def _invalidate_caches_for_event(self, event, backfilled, reset_state):
+        if reset_state:
+            self._get_current_state_for_key.invalidate_all()
+            self.get_rooms_for_user.invalidate_all()
+            self.get_users_in_room.invalidate((event.room_id,))
+            # self.get_joined_hosts_for_room.invalidate((event.room_id,))
+            self.get_room_name_and_aliases.invalidate((event.room_id,))
+
+        self._invalidate_get_event_cache(event.event_id)
+
+        self.get_latest_event_ids_in_room.invalidate((event.room_id,))
+
+        if not backfilled:
+            self._events_stream_cache.entity_has_changed(
+                event.room_id, event.internal_metadata.stream_ordering
+            )
+
+        # self.get_unread_event_push_actions_by_room_for_user.invalidate_many(
+        #     (event.room_id,)
+        # )
+
+        if event.type == EventTypes.Redaction:
+            self._invalidate_get_event_cache(event.redacts)
+
+        if event.type == EventTypes.Member:
+            self.get_rooms_for_user.invalidate((event.state_key,))
+            # self.get_joined_hosts_for_room.invalidate((event.room_id,))
+            self.get_users_in_room.invalidate((event.room_id,))
+            # self._membership_stream_cache.entity_has_changed(
+            #    event.state_key, event.internal_metadata.stream_ordering
+            # )
+
+        if not event.is_state():
+            return
+
+        if backfilled:
+            return
+
+        if (not event.internal_metadata.is_invite_from_remote()
+                and event.internal_metadata.is_outlier()):
+            return
+
+        self._get_current_state_for_key.invalidate((
+            event.room_id, event.type, event.state_key
+        ))
+
+        if event.type in [EventTypes.Name, EventTypes.Aliases]:
+            self.get_room_name_and_aliases.invalidate(
+                (event.room_id,)
+            )
+            pass
diff --git a/synapse/state.py b/synapse/state.py
index 1bca0f8f78..58211f5feb 100644
--- a/synapse/state.py
+++ b/synapse/state.py
@@ -75,7 +75,8 @@ class StateHandler(object):
         self._state_cache.start()
 
     @defer.inlineCallbacks
-    def get_current_state(self, room_id, event_type=None, state_key=""):
+    def get_current_state(self, room_id, event_type=None, state_key="",
+                          latest_event_ids=None):
         """ Retrieves the current state for the room. This is done by
         calling `get_latest_events_in_room` to get the leading edges of the
         event graph and then resolving any of the state conflicts.
@@ -89,9 +90,10 @@ class StateHandler(object):
         Returns:
             map from (type, state_key) to event
         """
-        event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
+        if not latest_event_ids:
+            latest_event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
 
-        res = yield self.resolve_state_groups(room_id, event_ids)
+        res = yield self.resolve_state_groups(room_id, latest_event_ids)
         state = res[1]
 
         if event_type:
diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index 57863bba4d..045ae6c03f 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -94,7 +94,8 @@ class DataStore(RoomMemberStore, RoomStore,
         )
 
         self._stream_id_gen = StreamIdGenerator(
-            db_conn, "events", "stream_ordering"
+            db_conn, "events", "stream_ordering",
+            extra_tables=[("local_invites", "stream_id")]
         )
         self._backfill_id_gen = StreamIdGenerator(
             db_conn, "events", "stream_ordering", step=-1
@@ -176,39 +177,6 @@ class DataStore(RoomMemberStore, RoomStore,
         self.__presence_on_startup = None
         return active_on_startup
 
-    def _get_cache_dict(self, db_conn, table, entity_column, stream_column, max_value):
-        # Fetch a mapping of room_id -> max stream position for "recent" rooms.
-        # It doesn't really matter how many we get, the StreamChangeCache will
-        # do the right thing to ensure it respects the max size of cache.
-        sql = (
-            "SELECT %(entity)s, MAX(%(stream)s) FROM %(table)s"
-            " WHERE %(stream)s > ? - 100000"
-            " GROUP BY %(entity)s"
-        ) % {
-            "table": table,
-            "entity": entity_column,
-            "stream": stream_column,
-        }
-
-        sql = self.database_engine.convert_param_style(sql)
-
-        txn = db_conn.cursor()
-        txn.execute(sql, (int(max_value),))
-        rows = txn.fetchall()
-        txn.close()
-
-        cache = {
-            row[0]: int(row[1])
-            for row in rows
-        }
-
-        if cache:
-            min_val = min(cache.values())
-        else:
-            min_val = max_value
-
-        return cache, min_val
-
     def _get_active_presence(self, db_conn):
         """Fetch non-offline presence from the database so that we can register
         the appropriate time outs.
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index b75b79df36..04d7fcf6d6 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -816,6 +816,40 @@ class SQLBaseStore(object):
             self._next_stream_id += 1
             return i
 
+    def _get_cache_dict(self, db_conn, table, entity_column, stream_column,
+                        max_value):
+        # Fetch a mapping of room_id -> max stream position for "recent" rooms.
+        # It doesn't really matter how many we get, the StreamChangeCache will
+        # do the right thing to ensure it respects the max size of cache.
+        sql = (
+            "SELECT %(entity)s, MAX(%(stream)s) FROM %(table)s"
+            " WHERE %(stream)s > ? - 100000"
+            " GROUP BY %(entity)s"
+        ) % {
+            "table": table,
+            "entity": entity_column,
+            "stream": stream_column,
+        }
+
+        sql = self.database_engine.convert_param_style(sql)
+
+        txn = db_conn.cursor()
+        txn.execute(sql, (int(max_value),))
+        rows = txn.fetchall()
+        txn.close()
+
+        cache = {
+            row[0]: int(row[1])
+            for row in rows
+        }
+
+        if cache:
+            min_val = min(cache.values())
+        else:
+            min_val = max_value
+
+        return cache, min_val
+
 
 class _RollbackButIsFineException(Exception):
     """ This exception is used to rollback a transaction without implying
diff --git a/synapse/storage/engines/__init__.py b/synapse/storage/engines/__init__.py
index a48230b93f..7bb5de1fe7 100644
--- a/synapse/storage/engines/__init__.py
+++ b/synapse/storage/engines/__init__.py
@@ -26,13 +26,13 @@ SUPPORTED_MODULE = {
 }
 
 
-def create_engine(config):
-    name = config.database_config["name"]
+def create_engine(database_config):
+    name = database_config["name"]
     engine_class = SUPPORTED_MODULE.get(name, None)
 
     if engine_class:
         module = importlib.import_module(name)
-        return engine_class(module, config=config)
+        return engine_class(module)
 
     raise RuntimeError(
         "Unsupported database engine '%s'" % (name,)
diff --git a/synapse/storage/engines/postgres.py b/synapse/storage/engines/postgres.py
index a09685b4df..c2290943b4 100644
--- a/synapse/storage/engines/postgres.py
+++ b/synapse/storage/engines/postgres.py
@@ -13,18 +13,15 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.storage.prepare_database import prepare_database
-
 from ._base import IncorrectDatabaseSetup
 
 
 class PostgresEngine(object):
     single_threaded = False
 
-    def __init__(self, database_module, config):
+    def __init__(self, database_module):
         self.module = database_module
         self.module.extensions.register_type(self.module.extensions.UNICODE)
-        self.config = config
 
     def check_database(self, txn):
         txn.execute("SHOW SERVER_ENCODING")
@@ -44,9 +41,6 @@ class PostgresEngine(object):
             self.module.extensions.ISOLATION_LEVEL_REPEATABLE_READ
         )
 
-    def prepare_database(self, db_conn):
-        prepare_database(db_conn, self, config=self.config)
-
     def is_deadlock(self, error):
         if isinstance(error, self.module.DatabaseError):
             return error.pgcode in ["40001", "40P01"]
diff --git a/synapse/storage/engines/sqlite3.py b/synapse/storage/engines/sqlite3.py
index 522b905949..14203aa500 100644
--- a/synapse/storage/engines/sqlite3.py
+++ b/synapse/storage/engines/sqlite3.py
@@ -13,9 +13,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.storage.prepare_database import (
-    prepare_database, prepare_sqlite3_database
-)
+from synapse.storage.prepare_database import prepare_database
 
 import struct
 
@@ -23,9 +21,8 @@ import struct
 class Sqlite3Engine(object):
     single_threaded = True
 
-    def __init__(self, database_module, config):
+    def __init__(self, database_module):
         self.module = database_module
-        self.config = config
 
     def check_database(self, txn):
         pass
@@ -34,13 +31,9 @@ class Sqlite3Engine(object):
         return sql
 
     def on_new_connection(self, db_conn):
-        self.prepare_database(db_conn)
+        prepare_database(db_conn, self, config=None)
         db_conn.create_function("rank", 1, _rank)
 
-    def prepare_database(self, db_conn):
-        prepare_sqlite3_database(db_conn)
-        prepare_database(db_conn, self, config=self.config)
-
     def is_deadlock(self, error):
         return False
 
diff --git a/synapse/storage/event_federation.py b/synapse/storage/event_federation.py
index 3489315e0d..0827946207 100644
--- a/synapse/storage/event_federation.py
+++ b/synapse/storage/event_federation.py
@@ -163,6 +163,22 @@ class EventFederationStore(SQLBaseStore):
             room_id,
         )
 
+    @defer.inlineCallbacks
+    def get_max_depth_of_events(self, event_ids):
+        sql = (
+            "SELECT MAX(depth) FROM events WHERE event_id IN (%s)"
+        ) % (",".join(["?"] * len(event_ids)),)
+
+        rows = yield self._execute(
+            "get_max_depth_of_events", None,
+            sql, *event_ids
+        )
+
+        if rows:
+            defer.returnValue(rows[0][0])
+        else:
+            defer.returnValue(1)
+
     def _get_min_depth_interaction(self, txn, room_id):
         min_depth = self._simple_select_one_onecol_txn(
             txn,
diff --git a/synapse/storage/events.py b/synapse/storage/events.py
index c4dc3b3d51..ee87a71719 100644
--- a/synapse/storage/events.py
+++ b/synapse/storage/events.py
@@ -367,7 +367,8 @@ class EventsStore(SQLBaseStore):
                 event
                 for event, _ in events_and_contexts
                 if event.type == EventTypes.Member
-            ]
+            ],
+            backfilled=backfilled,
         )
 
         def event_dict(event):
@@ -485,14 +486,8 @@ class EventsStore(SQLBaseStore):
             return
 
         for event, _ in state_events_and_contexts:
-            if (not event.internal_metadata.is_invite_from_remote()
-                    and event.internal_metadata.is_outlier()):
-                # Outlier events generally shouldn't clobber the current state.
-                # However invites from remote severs for rooms we aren't in
-                # are a bit special: they don't come with any associated
-                # state so are technically an outlier, however all the
-                # client-facing code assumes that they are in the current
-                # state table so we insert the event anyway.
+            if event.internal_metadata.is_outlier():
+                # Outlier events shouldn't clobber the current state.
                 continue
 
             if context.rejected:
@@ -1139,7 +1134,7 @@ class EventsStore(SQLBaseStore):
                     upper_bound = current_forward_id
 
                 sql = (
-                    "SELECT -event_stream_ordering FROM current_state_resets"
+                    "SELECT event_stream_ordering FROM current_state_resets"
                     " WHERE ? < event_stream_ordering"
                     " AND event_stream_ordering <= ?"
                     " ORDER BY event_stream_ordering ASC"
@@ -1148,7 +1143,7 @@ class EventsStore(SQLBaseStore):
                 state_resets = txn.fetchall()
 
                 sql = (
-                    "SELECT -event_stream_ordering, event_id, state_group"
+                    "SELECT event_stream_ordering, event_id, state_group"
                     " FROM ex_outlier_stream"
                     " WHERE ? > event_stream_ordering"
                     " AND event_stream_ordering >= ?"
diff --git a/synapse/storage/prepare_database.py b/synapse/storage/prepare_database.py
index 3f29aad1e8..00833422af 100644
--- a/synapse/storage/prepare_database.py
+++ b/synapse/storage/prepare_database.py
@@ -25,7 +25,7 @@ logger = logging.getLogger(__name__)
 
 # Remember to update this number every time a change is made to database
 # schema files, so the users will be informed on server restarts.
-SCHEMA_VERSION = 30
+SCHEMA_VERSION = 31
 
 dir_path = os.path.abspath(os.path.dirname(__file__))
 
@@ -53,6 +53,9 @@ class UpgradeDatabaseException(PrepareDatabaseException):
 def prepare_database(db_conn, database_engine, config):
     """Prepares a database for usage. Will either create all necessary tables
     or upgrade from an older schema version.
+
+    If `config` is None then prepare_database will assert that no upgrade is
+    necessary, *or* will create a fresh database if the database is empty.
     """
     try:
         cur = db_conn.cursor()
@@ -60,13 +63,18 @@ def prepare_database(db_conn, database_engine, config):
 
         if version_info:
             user_version, delta_files, upgraded = version_info
-            _upgrade_existing_database(
-                cur, user_version, delta_files, upgraded, database_engine, config
-            )
-        else:
-            _setup_new_database(cur, database_engine, config)
 
-        # cur.execute("PRAGMA user_version = %d" % (SCHEMA_VERSION,))
+            if config is None:
+                if user_version != SCHEMA_VERSION:
+                    # If we don't pass in a config file then we are expecting to
+                    # have already upgraded the DB.
+                    raise UpgradeDatabaseException("Database needs to be upgraded")
+            else:
+                _upgrade_existing_database(
+                    cur, user_version, delta_files, upgraded, database_engine, config
+                )
+        else:
+            _setup_new_database(cur, database_engine)
 
         cur.close()
         db_conn.commit()
@@ -75,7 +83,7 @@ def prepare_database(db_conn, database_engine, config):
         raise
 
 
-def _setup_new_database(cur, database_engine, config):
+def _setup_new_database(cur, database_engine):
     """Sets up the database by finding a base set of "full schemas" and then
     applying any necessary deltas.
 
@@ -148,12 +156,13 @@ def _setup_new_database(cur, database_engine, config):
         applied_delta_files=[],
         upgraded=False,
         database_engine=database_engine,
-        config=config,
+        config=None,
+        is_empty=True,
     )
 
 
 def _upgrade_existing_database(cur, current_version, applied_delta_files,
-                               upgraded, database_engine, config):
+                               upgraded, database_engine, config, is_empty=False):
     """Upgrades an existing database.
 
     Delta files can either be SQL stored in *.sql files, or python modules
@@ -246,7 +255,9 @@ def _upgrade_existing_database(cur, current_version, applied_delta_files,
                         module_name, absolute_path, python_file
                     )
                 logger.debug("Running script %s", relative_path)
-                module.run_upgrade(cur, database_engine, config=config)
+                module.run_create(cur, database_engine)
+                if not is_empty:
+                    module.run_upgrade(cur, database_engine, config=config)
             elif ext == ".pyc":
                 # Sometimes .pyc files turn up anyway even though we've
                 # disabled their generation; e.g. from distribution package
@@ -361,36 +372,3 @@ def _get_or_create_schema_state(txn, database_engine):
         return current_version, applied_deltas, upgraded
 
     return None
-
-
-def prepare_sqlite3_database(db_conn):
-    """This function should be called before `prepare_database` on sqlite3
-    databases.
-
-    Since we changed the way we store the current schema version and handle
-    updates to schemas, we need a way to upgrade from the old method to the
-    new. This only affects sqlite databases since they were the only ones
-    supported at the time.
-    """
-    with db_conn:
-        schema_path = os.path.join(
-            dir_path, "schema", "schema_version.sql",
-        )
-        create_schema = read_schema(schema_path)
-        db_conn.executescript(create_schema)
-
-        c = db_conn.execute("SELECT * FROM schema_version")
-        rows = c.fetchall()
-        c.close()
-
-        if not rows:
-            c = db_conn.execute("PRAGMA user_version")
-            row = c.fetchone()
-            c.close()
-
-            if row and row[0]:
-                db_conn.execute(
-                    "REPLACE INTO schema_version (version, upgraded)"
-                    " VALUES (?,?)",
-                    (row[0], False)
-                )
diff --git a/synapse/storage/receipts.py b/synapse/storage/receipts.py
index 4befebc8e2..7fdd84bbdc 100644
--- a/synapse/storage/receipts.py
+++ b/synapse/storage/receipts.py
@@ -160,8 +160,8 @@ class ReceiptsStore(SQLBaseStore):
             "content": content,
         }])
 
-    @cachedList(cache=get_linearized_receipts_for_room.cache, list_name="room_ids",
-                num_args=3, inlineCallbacks=True)
+    @cachedList(cached_method_name="get_linearized_receipts_for_room",
+                list_name="room_ids", num_args=3, inlineCallbacks=True)
     def _get_linearized_receipts_for_rooms(self, room_ids, to_key, from_key=None):
         if not room_ids:
             defer.returnValue({})
diff --git a/synapse/storage/registration.py b/synapse/storage/registration.py
index d46a963bb8..1f71773aaa 100644
--- a/synapse/storage/registration.py
+++ b/synapse/storage/registration.py
@@ -319,7 +319,7 @@ class RegistrationStore(SQLBaseStore):
 
         defer.returnValue(res if res else False)
 
-    @cachedList(cache=is_guest.cache, list_name="user_ids", num_args=1,
+    @cachedList(cached_method_name="is_guest", list_name="user_ids", num_args=1,
                 inlineCallbacks=True)
     def are_guests(self, user_ids):
         sql = "SELECT name, is_guest FROM users WHERE name IN (%s)" % (
diff --git a/synapse/storage/roommember.py b/synapse/storage/roommember.py
index 430b49c12e..66e7a40e3c 100644
--- a/synapse/storage/roommember.py
+++ b/synapse/storage/roommember.py
@@ -36,7 +36,7 @@ RoomsForUser = namedtuple(
 
 class RoomMemberStore(SQLBaseStore):
 
-    def _store_room_members_txn(self, txn, events):
+    def _store_room_members_txn(self, txn, events, backfilled):
         """Store a room member in the database.
         """
         self._simple_insert_many_txn(
@@ -62,6 +62,64 @@ class RoomMemberStore(SQLBaseStore):
                 self._membership_stream_cache.entity_has_changed,
                 event.state_key, event.internal_metadata.stream_ordering
             )
+            txn.call_after(
+                self.get_invited_rooms_for_user.invalidate, (event.state_key,)
+            )
+
+            # We update the local_invites table only if the event is "current",
+            # i.e., its something that has just happened.
+            # The only current event that can also be an outlier is if its an
+            # invite that has come in across federation.
+            is_new_state = not backfilled and (
+                not event.internal_metadata.is_outlier()
+                or event.internal_metadata.is_invite_from_remote()
+            )
+            is_mine = self.hs.is_mine_id(event.state_key)
+            if is_new_state and is_mine:
+                if event.membership == Membership.INVITE:
+                    self._simple_insert_txn(
+                        txn,
+                        table="local_invites",
+                        values={
+                            "event_id": event.event_id,
+                            "invitee": event.state_key,
+                            "inviter": event.sender,
+                            "room_id": event.room_id,
+                            "stream_id": event.internal_metadata.stream_ordering,
+                        }
+                    )
+                else:
+                    sql = (
+                        "UPDATE local_invites SET stream_id = ?, replaced_by = ? WHERE"
+                        " room_id = ? AND invitee = ? AND locally_rejected is NULL"
+                        " AND replaced_by is NULL"
+                    )
+
+                    txn.execute(sql, (
+                        event.internal_metadata.stream_ordering,
+                        event.event_id,
+                        event.room_id,
+                        event.state_key,
+                    ))
+
+    @defer.inlineCallbacks
+    def locally_reject_invite(self, user_id, room_id):
+        sql = (
+            "UPDATE local_invites SET stream_id = ?, locally_rejected = ? WHERE"
+            " room_id = ? AND invitee = ? AND locally_rejected is NULL"
+            " AND replaced_by is NULL"
+        )
+
+        def f(txn, stream_ordering):
+            txn.execute(sql, (
+                stream_ordering,
+                True,
+                room_id,
+                user_id,
+            ))
+
+        with self._stream_id_gen.get_next() as stream_ordering:
+            yield self.runInteraction("locally_reject_invite", f, stream_ordering)
 
     def get_room_member(self, user_id, room_id):
         """Retrieve the current state of a room member.
@@ -127,6 +185,24 @@ class RoomMemberStore(SQLBaseStore):
             user_id, [Membership.INVITE]
         )
 
+    @defer.inlineCallbacks
+    def get_invite_for_user_in_room(self, user_id, room_id):
+        """Gets the invite for the given user and room
+
+        Args:
+            user_id (str)
+            room_id (str)
+
+        Returns:
+            Deferred: Resolves to either a RoomsForUser or None if no invite was
+                found.
+        """
+        invites = yield self.get_invited_rooms_for_user(user_id)
+        for invite in invites:
+            if invite.room_id == room_id:
+                defer.returnValue(invite)
+        defer.returnValue(None)
+
     def get_leave_and_ban_events_for_user(self, user_id):
         """ Get all the leave events for a user
         Args:
@@ -163,29 +239,55 @@ class RoomMemberStore(SQLBaseStore):
 
     def _get_rooms_for_user_where_membership_is_txn(self, txn, user_id,
                                                     membership_list):
-        where_clause = "user_id = ? AND (%s) AND forgotten = 0" % (
-            " OR ".join(["membership = ?" for _ in membership_list]),
-        )
 
-        args = [user_id]
-        args.extend(membership_list)
+        do_invite = Membership.INVITE in membership_list
+        membership_list = [m for m in membership_list if m != Membership.INVITE]
 
-        sql = (
-            "SELECT m.room_id, m.sender, m.membership, m.event_id, e.stream_ordering"
-            " FROM current_state_events as c"
-            " INNER JOIN room_memberships as m"
-            " ON m.event_id = c.event_id"
-            " INNER JOIN events as e"
-            " ON e.event_id = c.event_id"
-            " AND m.room_id = c.room_id"
-            " AND m.user_id = c.state_key"
-            " WHERE %s"
-        ) % (where_clause,)
+        results = []
+        if membership_list:
+            where_clause = "user_id = ? AND (%s) AND forgotten = 0" % (
+                " OR ".join(["membership = ?" for _ in membership_list]),
+            )
 
-        txn.execute(sql, args)
-        return [
-            RoomsForUser(**r) for r in self.cursor_to_dict(txn)
-        ]
+            args = [user_id]
+            args.extend(membership_list)
+
+            sql = (
+                "SELECT m.room_id, m.sender, m.membership, m.event_id, e.stream_ordering"
+                " FROM current_state_events as c"
+                " INNER JOIN room_memberships as m"
+                " ON m.event_id = c.event_id"
+                " INNER JOIN events as e"
+                " ON e.event_id = c.event_id"
+                " AND m.room_id = c.room_id"
+                " AND m.user_id = c.state_key"
+                " WHERE %s"
+            ) % (where_clause,)
+
+            txn.execute(sql, args)
+            results = [
+                RoomsForUser(**r) for r in self.cursor_to_dict(txn)
+            ]
+
+        if do_invite:
+            sql = (
+                "SELECT i.room_id, inviter, i.event_id, e.stream_ordering"
+                " FROM local_invites as i"
+                " INNER JOIN events as e USING (event_id)"
+                " WHERE invitee = ? AND locally_rejected is NULL"
+                " AND replaced_by is NULL"
+            )
+
+            txn.execute(sql, (user_id,))
+            results.extend(RoomsForUser(
+                room_id=r["room_id"],
+                sender=r["inviter"],
+                event_id=r["event_id"],
+                stream_ordering=r["stream_ordering"],
+                membership=Membership.INVITE,
+            ) for r in self.cursor_to_dict(txn))
+
+        return results
 
     @cached(max_entries=5000)
     def get_joined_hosts_for_room(self, room_id):
diff --git a/synapse/storage/schema/delta/14/upgrade_appservice_db.py b/synapse/storage/schema/delta/14/upgrade_appservice_db.py
index 5c40a77757..8755bb2e49 100644
--- a/synapse/storage/schema/delta/14/upgrade_appservice_db.py
+++ b/synapse/storage/schema/delta/14/upgrade_appservice_db.py
@@ -18,7 +18,7 @@ import logging
 logger = logging.getLogger(__name__)
 
 
-def run_upgrade(cur, *args, **kwargs):
+def run_create(cur, *args, **kwargs):
     cur.execute("SELECT id, regex FROM application_services_regex")
     for row in cur.fetchall():
         try:
@@ -35,3 +35,7 @@ def run_upgrade(cur, *args, **kwargs):
                 "UPDATE application_services_regex SET regex=? WHERE id=?",
                 (new_regex, row[0])
             )
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/schema/delta/20/pushers.py b/synapse/storage/schema/delta/20/pushers.py
index 29164732af..147496a38b 100644
--- a/synapse/storage/schema/delta/20/pushers.py
+++ b/synapse/storage/schema/delta/20/pushers.py
@@ -27,7 +27,7 @@ import logging
 logger = logging.getLogger(__name__)
 
 
-def run_upgrade(cur, database_engine, *args, **kwargs):
+def run_create(cur, database_engine, *args, **kwargs):
     logger.info("Porting pushers table...")
     cur.execute("""
         CREATE TABLE IF NOT EXISTS pushers2 (
@@ -74,3 +74,7 @@ def run_upgrade(cur, database_engine, *args, **kwargs):
     cur.execute("DROP TABLE pushers")
     cur.execute("ALTER TABLE pushers2 RENAME TO pushers")
     logger.info("Moved %d pushers to new table", count)
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/schema/delta/25/fts.py b/synapse/storage/schema/delta/25/fts.py
index d3ff2b1779..4269ac69ad 100644
--- a/synapse/storage/schema/delta/25/fts.py
+++ b/synapse/storage/schema/delta/25/fts.py
@@ -43,7 +43,7 @@ SQLITE_TABLE = (
 )
 
 
-def run_upgrade(cur, database_engine, *args, **kwargs):
+def run_create(cur, database_engine, *args, **kwargs):
     if isinstance(database_engine, PostgresEngine):
         for statement in get_statements(POSTGRES_TABLE.splitlines()):
             cur.execute(statement)
@@ -76,3 +76,7 @@ def run_upgrade(cur, database_engine, *args, **kwargs):
         sql = database_engine.convert_param_style(sql)
 
         cur.execute(sql, ("event_search", progress_json))
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/schema/delta/27/ts.py b/synapse/storage/schema/delta/27/ts.py
index f8c16391a2..71b12a2731 100644
--- a/synapse/storage/schema/delta/27/ts.py
+++ b/synapse/storage/schema/delta/27/ts.py
@@ -27,7 +27,7 @@ ALTER_TABLE = (
 )
 
 
-def run_upgrade(cur, database_engine, *args, **kwargs):
+def run_create(cur, database_engine, *args, **kwargs):
     for statement in get_statements(ALTER_TABLE.splitlines()):
         cur.execute(statement)
 
@@ -55,3 +55,7 @@ def run_upgrade(cur, database_engine, *args, **kwargs):
         sql = database_engine.convert_param_style(sql)
 
         cur.execute(sql, ("event_origin_server_ts", progress_json))
+
+
+def run_upgrade(*args, **kwargs):
+    pass
diff --git a/synapse/storage/schema/delta/30/as_users.py b/synapse/storage/schema/delta/30/as_users.py
index 4f6e9dd540..b417e3ac08 100644
--- a/synapse/storage/schema/delta/30/as_users.py
+++ b/synapse/storage/schema/delta/30/as_users.py
@@ -18,7 +18,7 @@ from synapse.storage.appservice import ApplicationServiceStore
 logger = logging.getLogger(__name__)
 
 
-def run_upgrade(cur, database_engine, config, *args, **kwargs):
+def run_create(cur, database_engine, *args, **kwargs):
     # NULL indicates user was not registered by an appservice.
     try:
         cur.execute("ALTER TABLE users ADD COLUMN appservice_id TEXT")
@@ -26,6 +26,8 @@ def run_upgrade(cur, database_engine, config, *args, **kwargs):
         # Maybe we already added the column? Hope so...
         pass
 
+
+def run_upgrade(cur, database_engine, config, *args, **kwargs):
     cur.execute("SELECT name FROM users")
     rows = cur.fetchall()
 
diff --git a/synapse/storage/schema/delta/31/invites.sql b/synapse/storage/schema/delta/31/invites.sql
new file mode 100644
index 0000000000..2c57846d5a
--- /dev/null
+++ b/synapse/storage/schema/delta/31/invites.sql
@@ -0,0 +1,42 @@
+/* Copyright 2016 OpenMarket Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+CREATE TABLE local_invites(
+    stream_id BIGINT NOT NULL,
+    inviter TEXT NOT NULL,
+    invitee TEXT NOT NULL,
+    event_id TEXT NOT NULL,
+    room_id TEXT NOT NULL,
+    locally_rejected TEXT,
+    replaced_by TEXT
+);
+
+-- Insert all invites for local users into new `invites` table
+INSERT INTO local_invites SELECT
+        stream_ordering as stream_id,
+        sender as inviter,
+        state_key as invitee,
+        event_id,
+        room_id,
+        NULL as locally_rejected,
+        NULL as replaced_by
+    FROM events
+    NATURAL JOIN current_state_events
+    NATURAL JOIN room_memberships
+    WHERE membership = 'invite'  AND state_key IN (SELECT name FROM users);
+
+CREATE INDEX local_invites_id ON local_invites(stream_id);
+CREATE INDEX local_invites_for_user_idx ON local_invites(invitee, locally_rejected, replaced_by, room_id);
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index e9f9406014..c5d2a3a6df 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -273,8 +273,8 @@ class StateStore(SQLBaseStore):
             desc="_get_state_group_for_event",
         )
 
-    @cachedList(cache=_get_state_group_for_event.cache, list_name="event_ids",
-                num_args=1, inlineCallbacks=True)
+    @cachedList(cached_method_name="_get_state_group_for_event",
+                list_name="event_ids", num_args=1, inlineCallbacks=True)
     def _get_state_group_for_events(self, event_ids):
         """Returns mapping event_id -> state_group
         """
diff --git a/synapse/util/async.py b/synapse/util/async.py
index cd4d90f3cf..0d6f48e2d8 100644
--- a/synapse/util/async.py
+++ b/synapse/util/async.py
@@ -16,9 +16,13 @@
 
 from twisted.internet import defer, reactor
 
-from .logcontext import PreserveLoggingContext, preserve_fn
+from .logcontext import (
+    PreserveLoggingContext, preserve_fn, preserve_context_over_deferred,
+)
 from synapse.util import unwrapFirstError
 
+from contextlib import contextmanager
+
 
 @defer.inlineCallbacks
 def sleep(seconds):
@@ -137,3 +141,47 @@ def concurrently_execute(func, args, limit):
         preserve_fn(_concurrently_execute_inner)()
         for _ in xrange(limit)
     ], consumeErrors=True).addErrback(unwrapFirstError)
+
+
+class Linearizer(object):
+    """Linearizes access to resources based on a key. Useful to ensure only one
+    thing is happening at a time on a given resource.
+
+    Example:
+
+        with (yield linearizer.queue("test_key")):
+            # do some work.
+
+    """
+    def __init__(self):
+        self.key_to_defer = {}
+
+    @defer.inlineCallbacks
+    def queue(self, key):
+        # If there is already a deferred in the queue, we pull it out so that
+        # we can wait on it later.
+        # Then we replace it with a deferred that we resolve *after* the
+        # context manager has exited.
+        # We only return the context manager after the previous deferred has
+        # resolved.
+        # This all has the net effect of creating a chain of deferreds that
+        # wait for the previous deferred before starting their work.
+        current_defer = self.key_to_defer.get(key)
+
+        new_defer = defer.Deferred()
+        self.key_to_defer[key] = new_defer
+
+        if current_defer:
+            yield preserve_context_over_deferred(current_defer)
+
+        @contextmanager
+        def _ctx_manager():
+            try:
+                yield
+            finally:
+                new_defer.callback(None)
+                current_d = self.key_to_defer.get(key)
+                if current_d is new_defer:
+                    self.key_to_defer.pop(key, None)
+
+        defer.returnValue(_ctx_manager())
diff --git a/synapse/util/caches/descriptors.py b/synapse/util/caches/descriptors.py
index 35544b19fd..758f5982b0 100644
--- a/synapse/util/caches/descriptors.py
+++ b/synapse/util/caches/descriptors.py
@@ -167,7 +167,8 @@ class CacheDescriptor(object):
                 % (orig.__name__,)
             )
 
-        self.cache = Cache(
+    def __get__(self, obj, objtype=None):
+        cache = Cache(
             name=self.orig.__name__,
             max_entries=self.max_entries,
             keylen=self.num_args,
@@ -175,14 +176,12 @@ class CacheDescriptor(object):
             tree=self.tree,
         )
 
-    def __get__(self, obj, objtype=None):
-
         @functools.wraps(self.orig)
         def wrapped(*args, **kwargs):
             arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
             cache_key = tuple(arg_dict[arg_nm] for arg_nm in self.arg_names)
             try:
-                cached_result_d = self.cache.get(cache_key)
+                cached_result_d = cache.get(cache_key)
 
                 observer = cached_result_d.observe()
                 if DEBUG_CACHES:
@@ -204,7 +203,7 @@ class CacheDescriptor(object):
                 # Get the sequence number of the cache before reading from the
                 # database so that we can tell if the cache is invalidated
                 # while the SELECT is executing (SYN-369)
-                sequence = self.cache.sequence
+                sequence = cache.sequence
 
                 ret = defer.maybeDeferred(
                     preserve_context_over_fn,
@@ -213,20 +212,21 @@ class CacheDescriptor(object):
                 )
 
                 def onErr(f):
-                    self.cache.invalidate(cache_key)
+                    cache.invalidate(cache_key)
                     return f
 
                 ret.addErrback(onErr)
 
                 ret = ObservableDeferred(ret, consumeErrors=True)
-                self.cache.update(sequence, cache_key, ret)
+                cache.update(sequence, cache_key, ret)
 
                 return preserve_context_over_deferred(ret.observe())
 
-        wrapped.invalidate = self.cache.invalidate
-        wrapped.invalidate_all = self.cache.invalidate_all
-        wrapped.invalidate_many = self.cache.invalidate_many
-        wrapped.prefill = self.cache.prefill
+        wrapped.invalidate = cache.invalidate
+        wrapped.invalidate_all = cache.invalidate_all
+        wrapped.invalidate_many = cache.invalidate_many
+        wrapped.prefill = cache.prefill
+        wrapped.cache = cache
 
         obj.__dict__[self.orig.__name__] = wrapped
 
@@ -240,11 +240,12 @@ class CacheListDescriptor(object):
     the list of missing keys to the wrapped fucntion.
     """
 
-    def __init__(self, orig, cache, list_name, num_args=1, inlineCallbacks=False):
+    def __init__(self, orig, cached_method_name, list_name, num_args=1,
+                 inlineCallbacks=False):
         """
         Args:
             orig (function)
-            cache (Cache)
+            method_name (str); The name of the chached method.
             list_name (str): Name of the argument which is the bulk lookup list
             num_args (int)
             inlineCallbacks (bool): Whether orig is a generator that should
@@ -263,7 +264,7 @@ class CacheListDescriptor(object):
         self.arg_names = inspect.getargspec(orig).args[1:num_args + 1]
         self.list_pos = self.arg_names.index(self.list_name)
 
-        self.cache = cache
+        self.cached_method_name = cached_method_name
 
         self.sentinel = object()
 
@@ -277,11 +278,13 @@ class CacheListDescriptor(object):
         if self.list_name not in self.arg_names:
             raise Exception(
                 "Couldn't see arguments %r for %r."
-                % (self.list_name, cache.name,)
+                % (self.list_name, cached_method_name,)
             )
 
     def __get__(self, obj, objtype=None):
 
+        cache = getattr(obj, self.cached_method_name).cache
+
         @functools.wraps(self.orig)
         def wrapped(*args, **kwargs):
             arg_dict = inspect.getcallargs(self.orig, obj, *args, **kwargs)
@@ -297,14 +300,14 @@ class CacheListDescriptor(object):
                 key[self.list_pos] = arg
 
                 try:
-                    res = self.cache.get(tuple(key)).observe()
+                    res = cache.get(tuple(key)).observe()
                     res.addCallback(lambda r, arg: (arg, r), arg)
                     cached[arg] = res
                 except KeyError:
                     missing.append(arg)
 
             if missing:
-                sequence = self.cache.sequence
+                sequence = cache.sequence
                 args_to_call = dict(arg_dict)
                 args_to_call[self.list_name] = missing
 
@@ -327,10 +330,10 @@ class CacheListDescriptor(object):
 
                     key = list(keyargs)
                     key[self.list_pos] = arg
-                    self.cache.update(sequence, tuple(key), observer)
+                    cache.update(sequence, tuple(key), observer)
 
                     def invalidate(f, key):
-                        self.cache.invalidate(key)
+                        cache.invalidate(key)
                         return f
                     observer.addErrback(invalidate, tuple(key))
 
@@ -370,7 +373,7 @@ def cachedInlineCallbacks(max_entries=1000, num_args=1, lru=False, tree=False):
     )
 
 
-def cachedList(cache, list_name, num_args=1, inlineCallbacks=False):
+def cachedList(cached_method_name, list_name, num_args=1, inlineCallbacks=False):
     """Creates a descriptor that wraps a function in a `CacheListDescriptor`.
 
     Used to do batch lookups for an already created cache. A single argument
@@ -400,7 +403,7 @@ def cachedList(cache, list_name, num_args=1, inlineCallbacks=False):
     """
     return lambda orig: CacheListDescriptor(
         orig,
-        cache=cache,
+        cached_method_name=cached_method_name,
         list_name=list_name,
         num_args=num_args,
         inlineCallbacks=inlineCallbacks,
diff --git a/synapse/util/caches/response_cache.py b/synapse/util/caches/response_cache.py
index be310ba320..36686b479e 100644
--- a/synapse/util/caches/response_cache.py
+++ b/synapse/util/caches/response_cache.py
@@ -35,7 +35,7 @@ class ResponseCache(object):
             return None
 
     def set(self, key, deferred):
-        result = ObservableDeferred(deferred)
+        result = ObservableDeferred(deferred, consumeErrors=True)
         self.pending_result_cache[key] = result
 
         def remove(r):
diff --git a/tests/replication/slave/__init__.py b/tests/replication/slave/__init__.py
new file mode 100644
index 0000000000..b7df13c9ee
--- /dev/null
+++ b/tests/replication/slave/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/tests/replication/slave/storage/__init__.py b/tests/replication/slave/storage/__init__.py
new file mode 100644
index 0000000000..b7df13c9ee
--- /dev/null
+++ b/tests/replication/slave/storage/__init__.py
@@ -0,0 +1,14 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
diff --git a/tests/replication/slave/storage/_base.py b/tests/replication/slave/storage/_base.py
new file mode 100644
index 0000000000..0f525a8943
--- /dev/null
+++ b/tests/replication/slave/storage/_base.py
@@ -0,0 +1,57 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from twisted.internet import defer
+from tests import unittest
+
+from synapse.replication.slave.storage.events import SlavedEventStore
+
+from mock import Mock, NonCallableMock
+from tests.utils import setup_test_homeserver
+from synapse.replication.resource import ReplicationResource
+
+
+class BaseSlavedStoreTestCase(unittest.TestCase):
+    @defer.inlineCallbacks
+    def setUp(self):
+        self.hs = yield setup_test_homeserver(
+            "blue",
+            http_client=None,
+            replication_layer=Mock(),
+            ratelimiter=NonCallableMock(spec_set=[
+                "send_message",
+            ]),
+        )
+        self.hs.get_ratelimiter().send_message.return_value = (True, 0)
+
+        self.replication = ReplicationResource(self.hs)
+
+        self.master_store = self.hs.get_datastore()
+        self.slaved_store = SlavedEventStore(self.hs.get_db_conn(), self.hs)
+        self.event_id = 0
+
+    @defer.inlineCallbacks
+    def replicate(self):
+        streams = self.slaved_store.stream_positions()
+        result = yield self.replication.replicate(streams, 100)
+        yield self.slaved_store.process_replication(result)
+
+    @defer.inlineCallbacks
+    def check(self, method, args, expected_result=None):
+        master_result = yield getattr(self.master_store, method)(*args)
+        slaved_result = yield getattr(self.slaved_store, method)(*args)
+        self.assertEqual(master_result, slaved_result)
+        if expected_result is not None:
+            self.assertEqual(master_result, expected_result)
+            self.assertEqual(slaved_result, expected_result)
diff --git a/tests/replication/slave/storage/test_events.py b/tests/replication/slave/storage/test_events.py
new file mode 100644
index 0000000000..9af62702b3
--- /dev/null
+++ b/tests/replication/slave/storage/test_events.py
@@ -0,0 +1,258 @@
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ._base import BaseSlavedStoreTestCase
+
+from synapse.events import FrozenEvent, _EventInternalMetadata
+from synapse.events.snapshot import EventContext
+from synapse.storage.roommember import RoomsForUser
+
+from twisted.internet import defer
+
+
+USER_ID = "@feeling:blue"
+USER_ID_2 = "@bright:blue"
+OUTLIER = {"outlier": True}
+ROOM_ID = "!room:blue"
+
+
+def dict_equals(self, other):
+    return self.__dict__ == other.__dict__
+
+
+def patch__eq__(cls):
+    eq = getattr(cls, "__eq__", None)
+    cls.__eq__ = dict_equals
+
+    def unpatch():
+        if eq is not None:
+            cls.__eq__ = eq
+    return unpatch
+
+
+class SlavedEventStoreTestCase(BaseSlavedStoreTestCase):
+
+    def setUp(self):
+        # Patch up the equality operator for events so that we can check
+        # whether lists of events match using assertEquals
+        self.unpatches = [
+            patch__eq__(_EventInternalMetadata),
+            patch__eq__(FrozenEvent),
+        ]
+        return super(SlavedEventStoreTestCase, self).setUp()
+
+    def tearDown(self):
+        [unpatch() for unpatch in self.unpatches]
+
+    @defer.inlineCallbacks
+    def test_room_name_and_aliases(self):
+        create = yield self.persist(type="m.room.create", key="", creator=USER_ID)
+        yield self.persist(type="m.room.member", key=USER_ID, membership="join")
+        yield self.persist(type="m.room.name", key="", name="name1")
+        yield self.persist(
+            type="m.room.aliases", key="blue", aliases=["#1:blue"]
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_room_name_and_aliases", (ROOM_ID,), ("name1", ["#1:blue"])
+        )
+
+        # Set the room name.
+        yield self.persist(type="m.room.name", key="", name="name2")
+        yield self.replicate()
+        yield self.check(
+            "get_room_name_and_aliases", (ROOM_ID,), ("name2", ["#1:blue"])
+        )
+
+        # Set the room aliases.
+        yield self.persist(
+            type="m.room.aliases", key="blue", aliases=["#2:blue"]
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_room_name_and_aliases", (ROOM_ID,), ("name2", ["#2:blue"])
+        )
+
+        # Leave and join the room clobbering the state.
+        yield self.persist(type="m.room.member", key=USER_ID, membership="leave")
+        yield self.persist(
+            type="m.room.member", key=USER_ID, membership="join",
+            reset_state=[create]
+        )
+        yield self.replicate()
+
+        yield self.check(
+            "get_room_name_and_aliases", (ROOM_ID,), (None, [])
+        )
+
+    @defer.inlineCallbacks
+    def test_room_members(self):
+        create = yield self.persist(type="m.room.create", key="", creator=USER_ID)
+        yield self.replicate()
+        yield self.check("get_rooms_for_user", (USER_ID,), [])
+        yield self.check("get_users_in_room", (ROOM_ID,), [])
+
+        # Join the room.
+        join = yield self.persist(type="m.room.member", key=USER_ID, membership="join")
+        yield self.replicate()
+        yield self.check("get_rooms_for_user", (USER_ID,), [RoomsForUser(
+            room_id=ROOM_ID,
+            sender=USER_ID,
+            membership="join",
+            event_id=join.event_id,
+            stream_ordering=join.internal_metadata.stream_ordering,
+        )])
+        yield self.check("get_users_in_room", (ROOM_ID,), [USER_ID])
+
+        # Leave the room.
+        yield self.persist(type="m.room.member", key=USER_ID, membership="leave")
+        yield self.replicate()
+        yield self.check("get_rooms_for_user", (USER_ID,), [])
+        yield self.check("get_users_in_room", (ROOM_ID,), [])
+
+        # Add some other user to the room.
+        join = yield self.persist(type="m.room.member", key=USER_ID_2, membership="join")
+        yield self.replicate()
+        yield self.check("get_rooms_for_user", (USER_ID_2,), [RoomsForUser(
+            room_id=ROOM_ID,
+            sender=USER_ID,
+            membership="join",
+            event_id=join.event_id,
+            stream_ordering=join.internal_metadata.stream_ordering,
+        )])
+        yield self.check("get_users_in_room", (ROOM_ID,), [USER_ID_2])
+
+        # Join the room clobbering the state.
+        # This should remove any evidence of the other user being in the room.
+        yield self.persist(
+            type="m.room.member", key=USER_ID, membership="join",
+            reset_state=[create]
+        )
+        yield self.replicate()
+        yield self.check("get_users_in_room", (ROOM_ID,), [USER_ID])
+        yield self.check("get_rooms_for_user", (USER_ID_2,), [])
+
+    @defer.inlineCallbacks
+    def test_get_latest_event_ids_in_room(self):
+        create = yield self.persist(type="m.room.create", key="", creator=USER_ID)
+        yield self.replicate()
+        yield self.check(
+            "get_latest_event_ids_in_room", (ROOM_ID,), [create.event_id]
+        )
+
+        join = yield self.persist(
+            type="m.room.member", key=USER_ID, membership="join",
+            prev_events=[(create.event_id, {})],
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_latest_event_ids_in_room", (ROOM_ID,), [join.event_id]
+        )
+
+    @defer.inlineCallbacks
+    def test_get_current_state(self):
+        # Create the room.
+        create = yield self.persist(type="m.room.create", key="", creator=USER_ID)
+        yield self.replicate()
+        yield self.check(
+            "get_current_state_for_key", (ROOM_ID, "m.room.member", USER_ID), []
+        )
+
+        # Join the room.
+        join1 = yield self.persist(
+            type="m.room.member", key=USER_ID, membership="join",
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_current_state_for_key", (ROOM_ID, "m.room.member", USER_ID),
+            [join1]
+        )
+
+        # Add some other user to the room.
+        join2 = yield self.persist(
+            type="m.room.member", key=USER_ID_2, membership="join",
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_current_state_for_key", (ROOM_ID, "m.room.member", USER_ID_2),
+            [join2]
+        )
+
+        # Leave the room, then rejoin the room clobbering state.
+        yield self.persist(type="m.room.member", key=USER_ID, membership="leave")
+        join3 = yield self.persist(
+            type="m.room.member", key=USER_ID, membership="join",
+            reset_state=[create]
+        )
+        yield self.replicate()
+        yield self.check(
+            "get_current_state_for_key", (ROOM_ID, "m.room.member", USER_ID_2),
+            []
+        )
+        yield self.check(
+            "get_current_state_for_key", (ROOM_ID, "m.room.member", USER_ID),
+            [join3]
+        )
+
+    event_id = 0
+
+    @defer.inlineCallbacks
+    def persist(
+        self, sender=USER_ID, room_id=ROOM_ID, type={}, key=None, internal={},
+        state=None, reset_state=False, backfill=False,
+        depth=None, prev_events=[], auth_events=[], prev_state=[],
+        **content
+    ):
+        """
+        Returns:
+            synapse.events.FrozenEvent: The event that was persisted.
+        """
+        if depth is None:
+            depth = self.event_id
+
+        event_dict = {
+            "sender": sender,
+            "type": type,
+            "content": content,
+            "event_id": "$%d:blue" % (self.event_id,),
+            "room_id": room_id,
+            "depth": depth,
+            "origin_server_ts": self.event_id,
+            "prev_events": prev_events,
+            "auth_events": auth_events,
+        }
+        if key is not None:
+            event_dict["state_key"] = key
+            event_dict["prev_state"] = prev_state
+
+        event = FrozenEvent(event_dict, internal_metadata_dict=internal)
+
+        self.event_id += 1
+
+        context = EventContext(current_state=state)
+
+        ordering = None
+        if backfill:
+            yield self.master_store.persist_events(
+                [(event, context)], backfilled=True
+            )
+        else:
+            ordering, _ = yield self.master_store.persist_event(
+                event, context, current_state=reset_state
+            )
+
+        if ordering:
+            event.internal_metadata.stream_ordering = ordering
+
+        defer.returnValue(event)
diff --git a/tests/rest/client/v1/test_rooms.py b/tests/rest/client/v1/test_rooms.py
index 4ab8b35e6b..8853cbb5fc 100644
--- a/tests/rest/client/v1/test_rooms.py
+++ b/tests/rest/client/v1/test_rooms.py
@@ -259,8 +259,8 @@ class RoomPermissionsTestCase(RestTestCase):
         # set [invite/join/left] of self, set [invite/join/left] of other,
         # expect all 404s because room doesn't exist on any server
         for usr in [self.user_id, self.rmcreator_id]:
-            yield self.join(room=room, user=usr, expect_code=404)
-            yield self.leave(room=room, user=usr, expect_code=404)
+            yield self.join(room=room, user=usr, expect_code=403)
+            yield self.leave(room=room, user=usr, expect_code=403)
 
     @defer.inlineCallbacks
     def test_membership_private_room_perms(self):
diff --git a/tests/storage/test_base.py b/tests/storage/test_base.py
index 2e33beb07c..afbefb2e2d 100644
--- a/tests/storage/test_base.py
+++ b/tests/storage/test_base.py
@@ -53,7 +53,7 @@ class SQLBaseStoreTestCase(unittest.TestCase):
             "test",
             db_pool=self.db_pool,
             config=config,
-            database_engine=create_engine(config),
+            database_engine=create_engine(config.database_config),
         )
 
         self.datastore = SQLBaseStore(hs)
diff --git a/tests/util/test_linearizer.py b/tests/util/test_linearizer.py
new file mode 100644
index 0000000000..afcba482f9
--- /dev/null
+++ b/tests/util/test_linearizer.py
@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 OpenMarket Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+from tests import unittest
+
+from twisted.internet import defer
+
+from synapse.util.async import Linearizer
+
+
+class LinearizerTestCase(unittest.TestCase):
+
+    @defer.inlineCallbacks
+    def test_linearizer(self):
+        linearizer = Linearizer()
+
+        key = object()
+
+        d1 = linearizer.queue(key)
+        cm1 = yield d1
+
+        d2 = linearizer.queue(key)
+        self.assertFalse(d2.called)
+
+        with cm1:
+            self.assertFalse(d2.called)
+
+        self.assertTrue(d2.called)
+
+        with (yield d2):
+            pass
diff --git a/tests/utils.py b/tests/utils.py
index 52405502e9..c179df31ee 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -64,7 +64,7 @@ def setup_test_homeserver(name="test", datastore=None, config=None, **kargs):
         hs = HomeServer(
             name, db_pool=db_pool, config=config,
             version_string="Synapse/tests",
-            database_engine=create_engine(config),
+            database_engine=create_engine(config.database_config),
             get_db_conn=db_pool.get_db_conn,
             **kargs
         )
@@ -73,7 +73,7 @@ def setup_test_homeserver(name="test", datastore=None, config=None, **kargs):
         hs = HomeServer(
             name, db_pool=None, datastore=datastore, config=config,
             version_string="Synapse/tests",
-            database_engine=create_engine(config),
+            database_engine=create_engine(config.database_config),
             **kargs
         )
 
@@ -298,7 +298,7 @@ class SQLiteMemoryDbPool(ConnectionPool, object):
         return conn
 
     def create_engine(self):
-        return create_engine(self.config)
+        return create_engine(self.config.database_config)
 
 
 class MemoryDataStore(object):