diff --git a/app/controllers/settings/exports_controller.rb b/app/controllers/settings/exports_controller.rb
index cf874557602..7f76668d56f 100644
--- a/app/controllers/settings/exports_controller.rb
+++ b/app/controllers/settings/exports_controller.rb
@@ -9,11 +9,25 @@ class Settings::ExportsController < Settings::BaseController
   end
 
   def create
-    authorize :backup, :create?
+    raise Mastodon::NotPermittedError unless user_signed_in?
+
+    backup = nil
+
+    RedisLock.acquire(lock_options) do |lock|
+      if lock.acquired?
+        authorize :backup, :create?
+        backup = current_user.backups.create!
+      else
+        raise Mastodon::RaceConditionError
+      end
+    end
 
-    backup = current_user.backups.create!
     BackupWorker.perform_async(backup.id)
 
     redirect_to settings_export_path
   end
+
+  def lock_options
+    { redis: Redis.current, key: "backup:#{current_user.id}" }
+  end
 end
diff --git a/app/javascript/mastodon/actions/notifications.js b/app/javascript/mastodon/actions/notifications.js
index 4c145febc4f..61fef19e90b 100644
--- a/app/javascript/mastodon/actions/notifications.js
+++ b/app/javascript/mastodon/actions/notifications.js
@@ -92,7 +92,7 @@ export function updateNotifications(notification, intlMessages, intlLocale) {
 const excludeTypesFromSettings = state => state.getIn(['settings', 'notifications', 'shows']).filter(enabled => !enabled).keySeq().toJS();
 
 const excludeTypesFromFilter = filter => {
-  const allTypes = ImmutableList(['follow', 'favourite', 'reblog', 'mention']);
+  const allTypes = ImmutableList(['follow', 'favourite', 'reblog', 'mention', 'poll']);
   return allTypes.filterNot(item => item === filter).toJS();
 };
 
diff --git a/app/javascript/mastodon/features/notifications/components/notification.js b/app/javascript/mastodon/features/notifications/components/notification.js
index 9669b6e7def..61023bed603 100644
--- a/app/javascript/mastodon/features/notifications/components/notification.js
+++ b/app/javascript/mastodon/features/notifications/components/notification.js
@@ -205,6 +205,38 @@ class Notification extends ImmutablePureComponent {
     );
   }
 
+  renderPoll (notification) {
+    const { intl } = this.props;
+
+    return (
+      <HotKeys handlers={this.getHandlers()}>
+        <div className='notification notification-poll focusable' tabIndex='0' aria-label={notificationForScreenReader(intl, intl.formatMessage({ id: 'notification.poll', defaultMessage: 'Your poll has ended' }), notification.get('created_at'))}>
+          <div className='notification__message'>
+            <div className='notification__favourite-icon-wrapper'>
+              <Icon id='tasks' fixedWidth />
+            </div>
+
+            <span title={notification.get('created_at')}>
+              <FormattedMessage id='notification.poll' defaultMessage='Your poll has ended' />
+            </span>
+          </div>
+
+          <StatusContainer
+            id={notification.get('status')}
+            account={notification.get('account')}
+            muted
+            withDismiss
+            hidden={this.props.hidden}
+            getScrollPosition={this.props.getScrollPosition}
+            updateScrollBottom={this.props.updateScrollBottom}
+            cachedMediaWidth={this.props.cachedMediaWidth}
+            cacheMediaWidth={this.props.cacheMediaWidth}
+          />
+        </div>
+      </HotKeys>
+    );
+  }
+
   render () {
     const { notification } = this.props;
     const account          = notification.get('account');
@@ -220,6 +252,8 @@ class Notification extends ImmutablePureComponent {
       return this.renderFavourite(notification, link);
     case 'reblog':
       return this.renderReblog(notification, link);
+    case 'poll':
+      return this.renderPoll(notification);
     }
 
     return null;
diff --git a/app/javascript/mastodon/locales/en.json b/app/javascript/mastodon/locales/en.json
index ae37322e801..822c1ee50f5 100644
--- a/app/javascript/mastodon/locales/en.json
+++ b/app/javascript/mastodon/locales/en.json
@@ -245,6 +245,7 @@
   "notification.favourite": "{name} favourited your status",
   "notification.follow": "{name} followed you",
   "notification.mention": "{name} mentioned you",
+  "notification.poll": "Your poll has ended",
   "notification.reblog": "{name} boosted your status",
   "notifications.clear": "Clear notifications",
   "notifications.clear_confirmation": "Are you sure you want to permanently clear all your notifications?",
diff --git a/app/javascript/mastodon/reducers/settings.js b/app/javascript/mastodon/reducers/settings.js
index 2e1878cf782..a0eea137f11 100644
--- a/app/javascript/mastodon/reducers/settings.js
+++ b/app/javascript/mastodon/reducers/settings.js
@@ -31,6 +31,7 @@ const initialState = ImmutableMap({
       favourite: true,
       reblog: true,
       mention: true,
+      poll: true,
     }),
 
     quickFilter: ImmutableMap({
@@ -44,6 +45,7 @@ const initialState = ImmutableMap({
       favourite: true,
       reblog: true,
       mention: true,
+      poll: true,
     }),
 
     sounds: ImmutableMap({
@@ -51,6 +53,7 @@ const initialState = ImmutableMap({
       favourite: true,
       reblog: true,
       mention: true,
+      poll: true,
     }),
   }),
 
diff --git a/app/javascript/mastodon/service_worker/web_push_locales.js b/app/javascript/mastodon/service_worker/web_push_locales.js
index ce96ae297c5..5ce8c7b50a1 100644
--- a/app/javascript/mastodon/service_worker/web_push_locales.js
+++ b/app/javascript/mastodon/service_worker/web_push_locales.js
@@ -18,6 +18,7 @@ filenames.forEach(filename => {
     'notification.follow': full['notification.follow'] || '',
     'notification.mention': full['notification.mention'] || '',
     'notification.reblog': full['notification.reblog'] || '',
+    'notification.poll': full['notification.poll'] || '',
 
     'status.show_more': full['status.show_more'] || '',
     'status.reblog': full['status.reblog'] || '',
diff --git a/app/lib/activitypub/activity/create.rb b/app/lib/activitypub/activity/create.rb
index 7e4e57eadda..b49806ecd04 100644
--- a/app/lib/activitypub/activity/create.rb
+++ b/app/lib/activitypub/activity/create.rb
@@ -243,6 +243,8 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
     return false if replied_to_status.nil? || replied_to_status.poll.nil? || !replied_to_status.local? || !replied_to_status.poll.options.include?(@object['name'])
     return true if replied_to_status.poll.expired?
     replied_to_status.poll.votes.create!(account: @account, choice: replied_to_status.poll.options.index(@object['name']), uri: @object['id'])
+    ActivityPub::DistributePollUpdateWorker.perform_in(3.minutes, replied_to_status.id) unless replied_to_status.poll.hide_totals
+    true
   end
 
   def resolve_thread(status)
diff --git a/app/lib/activitypub/activity/update.rb b/app/lib/activitypub/activity/update.rb
index 67dae3f8138..5f15f527452 100644
--- a/app/lib/activitypub/activity/update.rb
+++ b/app/lib/activitypub/activity/update.rb
@@ -5,6 +5,7 @@ class ActivityPub::Activity::Update < ActivityPub::Activity
 
   def perform
     update_account if equals_or_includes_any?(@object['type'], SUPPORTED_TYPES)
+    update_poll if equals_or_includes_any?(@object['type'], %w(Question))
   end
 
   private
@@ -14,4 +15,14 @@ class ActivityPub::Activity::Update < ActivityPub::Activity
 
     ActivityPub::ProcessAccountService.new.call(@account.username, @account.domain, @object, signed_with_known_key: true)
   end
+
+  def update_poll
+    return reject_payload! if invalid_origin?(@object['id'])
+    status = Status.find_by(uri: object_uri, account_id: @account.id)
+    return if status.nil? || status.poll_id.nil?
+    poll = Poll.find(status.poll_id)
+    return if poll.nil?
+
+    ActivityPub::ProcessPollService.new.call(poll, @object)
+  end
 end
diff --git a/app/models/notification.rb b/app/models/notification.rb
index 2f0a9b78c7a..982136c0549 100644
--- a/app/models/notification.rb
+++ b/app/models/notification.rb
@@ -22,6 +22,7 @@ class Notification < ApplicationRecord
     follow:         'Follow',
     follow_request: 'FollowRequest',
     favourite:      'Favourite',
+    poll:           'Poll',
   }.freeze
 
   STATUS_INCLUDES = [:account, :application, :media_attachments, :tags, active_mentions: :account, reblog: [:account, :application, :media_attachments, :tags, active_mentions: :account]].freeze
@@ -35,6 +36,7 @@ class Notification < ApplicationRecord
   belongs_to :follow,         foreign_type: 'Follow',        foreign_key: 'activity_id', optional: true
   belongs_to :follow_request, foreign_type: 'FollowRequest', foreign_key: 'activity_id', optional: true
   belongs_to :favourite,      foreign_type: 'Favourite',     foreign_key: 'activity_id', optional: true
+  belongs_to :poll,           foreign_type: 'Poll',          foreign_key: 'activity_id', optional: true
 
   validates :account_id, uniqueness: { scope: [:activity_type, :activity_id] }
   validates :activity_type, inclusion: { in: TYPE_CLASS_MAP.values }
@@ -44,7 +46,7 @@ class Notification < ApplicationRecord
     where(activity_type: types)
   }
 
-  cache_associated :from_account, status: STATUS_INCLUDES, mention: [status: STATUS_INCLUDES], favourite: [:account, status: STATUS_INCLUDES], follow: :account
+  cache_associated :from_account, status: STATUS_INCLUDES, mention: [status: STATUS_INCLUDES], favourite: [:account, status: STATUS_INCLUDES], follow: :account, poll: [status: STATUS_INCLUDES]
 
   def type
     @type ||= TYPE_CLASS_MAP.invert[activity_type].to_sym
@@ -58,6 +60,8 @@ class Notification < ApplicationRecord
       favourite&.status
     when :mention
       mention&.status
+    when :poll
+      poll&.status
     end
   end
 
@@ -97,7 +101,7 @@ class Notification < ApplicationRecord
     return unless new_record?
 
     case activity_type
-    when 'Status', 'Follow', 'Favourite', 'FollowRequest'
+    when 'Status', 'Follow', 'Favourite', 'FollowRequest', 'Poll'
       self.from_account_id = activity&.account_id
     when 'Mention'
       self.from_account_id = activity&.status&.account_id
diff --git a/app/serializers/activitypub/update_poll_serializer.rb b/app/serializers/activitypub/update_poll_serializer.rb
new file mode 100644
index 00000000000..f7933346feb
--- /dev/null
+++ b/app/serializers/activitypub/update_poll_serializer.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+class ActivityPub::UpdatePollSerializer < ActiveModel::Serializer
+  attributes :id, :type, :actor, :to
+
+  has_one :object, serializer: ActivityPub::NoteSerializer
+
+  def id
+    [ActivityPub::TagManager.instance.uri_for(object), '#updates/', object.poll.updated_at.to_i].join
+  end
+
+  def type
+    'Update'
+  end
+
+  def actor
+    ActivityPub::TagManager.instance.uri_for(object)
+  end
+
+  def to
+    ActivityPub::TagManager.instance.to(object)
+  end
+
+  def cc
+    ActivityPub::TagManager.instance.cc(object)
+  end
+end
diff --git a/app/serializers/rest/notification_serializer.rb b/app/serializers/rest/notification_serializer.rb
index 541a6b8b5c4..80812ad0df9 100644
--- a/app/serializers/rest/notification_serializer.rb
+++ b/app/serializers/rest/notification_serializer.rb
@@ -11,6 +11,6 @@ class REST::NotificationSerializer < ActiveModel::Serializer
   end
 
   def status_type?
-    [:favourite, :reblog, :mention].include?(object.type)
+    [:favourite, :reblog, :mention, :poll].include?(object.type)
   end
 end
diff --git a/app/services/activitypub/fetch_remote_poll_service.rb b/app/services/activitypub/fetch_remote_poll_service.rb
index 4f9814fcd7e..44a23712c31 100644
--- a/app/services/activitypub/fetch_remote_poll_service.rb
+++ b/app/services/activitypub/fetch_remote_poll_service.rb
@@ -4,54 +4,7 @@ class ActivityPub::FetchRemotePollService < BaseService
   include JsonLdHelper
 
   def call(poll, on_behalf_of = nil)
-    @json = fetch_resource(poll.status.uri, true, on_behalf_of)
-
-    return unless supported_context? && expected_type?
-
-    expires_at = begin
-      if @json['closed'].is_a?(String)
-        @json['closed']
-      elsif !@json['closed'].nil? && !@json['closed'].is_a?(FalseClass)
-        Time.now.utc
-      else
-        @json['endTime']
-      end
-    end
-
-    items = begin
-      if @json['anyOf'].is_a?(Array)
-        @json['anyOf']
-      else
-        @json['oneOf']
-      end
-    end
-
-    latest_options = items.map { |item| item['name'].presence || item['content'] }
-
-    # If for some reasons the options were changed, it invalidates all previous
-    # votes, so we need to remove them
-    poll.votes.delete_all if latest_options != poll.options
-
-    begin
-      poll.update!(
-        last_fetched_at: Time.now.utc,
-        expires_at: expires_at,
-        options: latest_options,
-        cached_tallies: items.map { |item| item.dig('replies', 'totalItems') || 0 }
-      )
-    rescue ActiveRecord::StaleObjectError
-      poll.reload
-      retry
-    end
-  end
-
-  private
-
-  def supported_context?
-    super(@json)
-  end
-
-  def expected_type?
-    equals_or_includes_any?(@json['type'], %w(Question))
+    json = fetch_resource(poll.status.uri, true, on_behalf_of)
+    ActivityPub::ProcessPollService.new.call(poll, json)
   end
 end
diff --git a/app/services/activitypub/process_poll_service.rb b/app/services/activitypub/process_poll_service.rb
new file mode 100644
index 00000000000..ee248169d9d
--- /dev/null
+++ b/app/services/activitypub/process_poll_service.rb
@@ -0,0 +1,64 @@
+# frozen_string_literal: true
+
+class ActivityPub::ProcessPollService < BaseService
+  include JsonLdHelper
+
+  def call(poll, json)
+    @json = json
+    return unless supported_context? && expected_type?
+
+    previous_expires_at = poll.expires_at
+
+    expires_at = begin
+      if @json['closed'].is_a?(String)
+        @json['closed']
+      elsif !@json['closed'].nil? && !@json['closed'].is_a?(FalseClass)
+        Time.now.utc
+      else
+        @json['endTime']
+      end
+    end
+
+    items = begin
+      if @json['anyOf'].is_a?(Array)
+        @json['anyOf']
+      else
+        @json['oneOf']
+      end
+    end
+
+    latest_options = items.map { |item| item['name'].presence || item['content'] }
+
+    # If for some reasons the options were changed, it invalidates all previous
+    # votes, so we need to remove them
+    poll.votes.delete_all if latest_options != poll.options
+
+    begin
+      poll.update!(
+        last_fetched_at: Time.now.utc,
+        expires_at: expires_at,
+        options: latest_options,
+        cached_tallies: items.map { |item| item.dig('replies', 'totalItems') || 0 }
+      )
+    rescue ActiveRecord::StaleObjectError
+      poll.reload
+      retry
+    end
+
+    # If the poll had no expiration date set but now has, and people have voted,
+    # schedule a notification.
+    if previous_expires_at.nil? && poll.expires_at.present? && poll.votes.exists?
+      PollExpirationNotifyWorker.perform_at(poll.expires_at + 5.minutes, poll.id)
+    end
+  end
+
+  private
+
+  def supported_context?
+    super(@json)
+  end
+
+  def expected_type?
+    equals_or_includes_any?(@json['type'], %w(Question))
+  end
+end
diff --git a/app/services/notify_service.rb b/app/services/notify_service.rb
index b80ceef03c2..7a86879f0a2 100644
--- a/app/services/notify_service.rb
+++ b/app/services/notify_service.rb
@@ -38,6 +38,10 @@ class NotifyService < BaseService
     false
   end
 
+  def blocked_poll?
+    false
+  end
+
   def following_sender?
     return @following_sender if defined?(@following_sender)
     @following_sender = @recipient.following?(@notification.from_account) || @recipient.requested?(@notification.from_account)
@@ -88,7 +92,7 @@ class NotifyService < BaseService
 
   def blocked?
     blocked   = @recipient.suspended?                            # Skip if the recipient account is suspended anyway
-    blocked ||= from_self?                                       # Skip for interactions with self
+    blocked ||= from_self? unless @notification.type == :poll    # Skip for interactions with self
 
     return blocked if message? && from_staff?
 
diff --git a/app/services/post_status_service.rb b/app/services/post_status_service.rb
index 8a9d26c5629..b9952369d89 100644
--- a/app/services/post_status_service.rb
+++ b/app/services/post_status_service.rb
@@ -91,10 +91,13 @@ class PostStatusService < BaseService
   def postprocess_status!
     LinkCrawlWorker.perform_async(@status.id) unless @status.spoiler_text?
     DistributionWorker.perform_async(@status.id)
+
     unless @status.local_only?
       Pubsubhubbub::DistributionWorker.perform_async(@status.stream_entry.id)
       ActivityPub::DistributionWorker.perform_async(@status.id)
     end
+
+    PollExpirationNotifyWorker.perform_at(@status.poll.expires_at, @status.poll.id) if @status.poll
   end
 
   def validate_media!
diff --git a/app/services/vote_service.rb b/app/services/vote_service.rb
index 5b80da03a37..34a1fe2aad7 100644
--- a/app/services/vote_service.rb
+++ b/app/services/vote_service.rb
@@ -19,14 +19,17 @@ class VoteService < BaseService
       end
     end
 
-    return if @poll.account.local?
-
-    @votes.each do |vote|
-      ActivityPub::DeliveryWorker.perform_async(
-        build_json(vote),
-        @account.id,
-        @poll.account.inbox_url
-      )
+    if @poll.account.local?
+      ActivityPub::DistributePollUpdateWorker.perform_in(3.minutes, @poll.status.id) unless @poll.hide_totals
+    else
+      @votes.each do |vote|
+        ActivityPub::DeliveryWorker.perform_async(
+          build_json(vote),
+          @account.id,
+          @poll.account.inbox_url
+        )
+      end
+      PollExpirationNotifyWorker.perform_at(@poll.expires_at + 5.minutes, @poll.id) unless @poll.expires_at.nil?
     end
   end
 
diff --git a/app/workers/activitypub/distribute_poll_update_worker.rb b/app/workers/activitypub/distribute_poll_update_worker.rb
new file mode 100644
index 00000000000..718279c1ba6
--- /dev/null
+++ b/app/workers/activitypub/distribute_poll_update_worker.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+class ActivityPub::DistributePollUpdateWorker
+  include Sidekiq::Worker
+
+  sidekiq_options queue: 'push', unique: :until_executed, retry: 0
+
+  def perform(status_id)
+    @status  = Status.find(status_id)
+    @account = @status.account
+
+    return unless @status.poll
+
+    ActivityPub::DeliveryWorker.push_bulk(inboxes) do |inbox_url|
+      [payload, @account.id, inbox_url]
+    end
+
+    relay! if relayable?
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+
+  private
+
+  def relayable?
+    @status.public_visibility?
+  end
+
+  def inboxes
+    return @inboxes if defined?(@inboxes)
+    target_accounts = @status.mentions.map(&:account).reject(&:local?)
+    target_accounts += @status.reblogs.map(&:account).reject(&:local?)
+    target_accounts += @status.poll.votes.map(&:account).reject(&:local?)
+    target_accounts.uniq!(&:id)
+    @inboxes = target_accounts.select(&:activitypub?).pluck(&:inbox_url)
+    @inboxes += @account.followers.inboxes unless @status.direct_visibility?
+    @inboxes.uniq!
+    @inboxes
+  end
+
+  def signed_payload
+    Oj.dump(ActivityPub::LinkedDataSignature.new(unsigned_payload).sign!(@account))
+  end
+
+  def unsigned_payload
+    ActiveModelSerializers::SerializableResource.new(
+      @status,
+      serializer: ActivityPub::UpdatePollSerializer,
+      adapter: ActivityPub::Adapter
+    ).as_json
+  end
+
+  def payload
+    @payload ||= @status.distributable? ? signed_payload : Oj.dump(unsigned_payload)
+  end
+
+  def relay!
+    ActivityPub::DeliveryWorker.push_bulk(Relay.enabled.pluck(:inbox_url)) do |inbox_url|
+      [payload, @account.id, inbox_url]
+    end
+  end
+end
diff --git a/app/workers/poll_expiration_notify_worker.rb b/app/workers/poll_expiration_notify_worker.rb
new file mode 100644
index 00000000000..ae72298b808
--- /dev/null
+++ b/app/workers/poll_expiration_notify_worker.rb
@@ -0,0 +1,24 @@
+# frozen_string_literal: true
+
+class PollExpirationNotifyWorker
+  include Sidekiq::Worker
+
+  sidekiq_options unique: :until_executed
+
+  def perform(poll_id)
+    poll = Poll.find(poll_id)
+
+    # Notify poll owner and remote voters
+    if poll.local?
+      ActivityPub::DistributePollUpdateWorker.perform_async(poll.status.id)
+      NotifyService.new.call(poll.account, poll)
+    end
+
+    # Notify local voters
+    poll.votes.includes(:account).map(&:account).filter(&:local?).each do |account|
+      NotifyService.new.call(account, poll)
+    end
+  rescue ActiveRecord::RecordNotFound
+    true
+  end
+end
diff --git a/streaming/index.js b/streaming/index.js
index 869186934e7..d4fb8cad38e 100644
--- a/streaming/index.js
+++ b/streaming/index.js
@@ -89,7 +89,6 @@ const startWorker = (workerId) => {
       host:     process.env.DB_HOST || pg.defaults.host,
       port:     process.env.DB_PORT || pg.defaults.port,
       max:      10,
-      ssl:      !!process.env.DB_SSLMODE && process.env.DB_SSLMODE !== 'disable' ? true : undefined,
     },
 
     production: {
@@ -99,11 +98,15 @@ const startWorker = (workerId) => {
       host:     process.env.DB_HOST || 'localhost',
       port:     process.env.DB_PORT || 5432,
       max:      10,
-      ssl:      !!process.env.DB_SSLMODE && process.env.DB_SSLMODE !== 'disable' ? true : undefined,
     },
   };
 
-  const app    = express();
+  if (!!process.env.DB_SSLMODE && process.env.DB_SSLMODE !== 'disable') {
+    pgConfigs.development.ssl = true;
+    pgConfigs.production.ssl  = true;
+  }
+
+  const app = express();
   app.set('trusted proxy', process.env.TRUSTED_PROXY_IP || 'loopback,uniquelocal');
 
   const pgPool = new pg.Pool(Object.assign(pgConfigs[env], dbUrlToConfig(process.env.DATABASE_URL)));