diff --git a/app/helpers/atom_builder_helper.rb b/app/helpers/atom_builder_helper.rb
deleted file mode 100644
index 185388ec93c..00000000000
--- a/app/helpers/atom_builder_helper.rb
+++ /dev/null
@@ -1,285 +0,0 @@
-# frozen_string_literal: true
-
-module AtomBuilderHelper
-  def stream_updated_at
-    if @account.stream_entries.last
-      (@account.updated_at > @account.stream_entries.last.created_at ? @account.updated_at : @account.stream_entries.last.created_at)
-    else
-      @account.updated_at
-    end
-  end
-
-  def entry(xml, is_root = false, &block)
-    if is_root
-      root_tag(xml, :entry, &block)
-    else
-      xml.entry(&block)
-    end
-  end
-
-  def feed(xml, &block)
-    root_tag(xml, :feed, &block)
-  end
-
-  def unique_id(xml, date, id, type)
-    xml.id_ TagManager.instance.unique_tag(date, id, type)
-  end
-
-  def simple_id(xml, id)
-    xml.id_ id
-  end
-
-  def published_at(xml, date)
-    xml.published date.iso8601
-  end
-
-  def updated_at(xml, date)
-    xml.updated date.iso8601
-  end
-
-  def verb(xml, verb)
-    xml['activity'].send('verb', TagManager::VERBS[verb])
-  end
-
-  def content(xml, content, warning = nil)
-    xml.summary(warning) unless warning.blank?
-    xml.content({ type: 'html' }, content) unless content.blank?
-  end
-
-  def title(xml, title)
-    xml.title strip_tags(title || '').truncate(80)
-  end
-
-  def author(xml, &block)
-    xml.author(&block)
-  end
-
-  def category(xml, term)
-    xml.category(term: term)
-  end
-
-  def target(xml, &block)
-    xml['activity'].object(&block)
-  end
-
-  def object_type(xml, type)
-    xml['activity'].send('object-type', TagManager::TYPES[type])
-  end
-
-  def uri(xml, uri)
-    xml.uri uri
-  end
-
-  def name(xml, name)
-    xml.name name
-  end
-
-  def summary(xml, summary)
-    xml.summary(summary) unless summary.blank?
-  end
-
-  def subtitle(xml, subtitle)
-    xml.subtitle(subtitle) unless subtitle.blank?
-  end
-
-  def link_alternate(xml, url)
-    xml.link(rel: 'alternate', type: 'text/html', href: url)
-  end
-
-  def link_self(xml, url)
-    xml.link(rel: 'self', type: 'application/atom+xml', href: url)
-  end
-
-  def link_next(xml, url)
-    xml.link(rel: 'next', type: 'application/atom+xml', href: url)
-  end
-
-  def link_hub(xml, url)
-    xml.link(rel: 'hub', href: url)
-  end
-
-  def link_salmon(xml, url)
-    xml.link(rel: 'salmon', href: url)
-  end
-
-  def portable_contact(xml, account)
-    xml['poco'].preferredUsername account.username
-    xml['poco'].displayName(account.display_name) unless account.display_name.blank?
-    xml['poco'].note(Formatter.instance.simplified_format(account)) unless account.note.blank?
-  end
-
-  def in_reply_to(xml, uri, url)
-    xml['thr'].send('in-reply-to', ref: uri, href: url, type: 'text/html')
-  end
-
-  def link_mention(xml, account)
-    xml.link(:rel => 'mentioned', :href => TagManager.instance.uri_for(account), 'ostatus:object-type' => TagManager::TYPES[:person])
-  end
-
-  def link_enclosure(xml, media)
-    xml.link(rel: 'enclosure', href: full_asset_url(media.file.url(:original, false)), type: media.file_content_type, length: media.file_file_size)
-  end
-
-  def link_avatar(xml, account)
-    single_link_avatar(xml, account, :original, 120)
-  end
-
-  def link_header(xml, account)
-    xml.link('rel' => 'header', 'type' => account.header_content_type, 'media:width' => 700, 'media:height' => 335, 'href' => full_asset_url(account.header.url(:original)))
-  end
-
-  def logo(xml, url)
-    xml.logo url
-  end
-
-  def email(xml, email)
-    xml.email email
-  end
-
-  def conditionally_formatted(activity)
-    if activity.is_a?(Status)
-      Formatter.instance.format(activity.reblog? ? activity.reblog : activity)
-    elsif activity.nil?
-      nil
-    else
-      activity.content
-    end
-  end
-
-  def link_visibility(xml, item)
-    return unless item.respond_to?(:visibility) && item.public_visibility?
-    xml.link(:rel => 'mentioned', :href => TagManager::COLLECTIONS[:public], 'ostatus:object-type' => TagManager::TYPES[:collection])
-  end
-
-  def privacy_scope(xml, level)
-    xml['mastodon'].scope(level)
-  end
-
-  def include_author(xml, account)
-    simple_id        xml, TagManager.instance.uri_for(account)
-    object_type      xml, :person
-    uri              xml, TagManager.instance.uri_for(account)
-    name             xml, account.username
-    email            xml, account.local? ? account.local_username_and_domain : account.acct
-    summary          xml, account.note
-    link_alternate   xml, TagManager.instance.url_for(account)
-    link_avatar      xml, account
-    link_header      xml, account
-    portable_contact xml, account
-    privacy_scope    xml, account.locked? ? :private : :public
-  end
-
-  def rich_content(xml, activity)
-    if activity.is_a?(Status)
-      content xml, conditionally_formatted(activity), activity.spoiler_text
-    else
-      content xml, conditionally_formatted(activity)
-    end
-  end
-
-  def include_target(xml, target)
-    simple_id xml, TagManager.instance.uri_for(target)
-
-    if target.object_type == :person
-      include_author xml, target
-    else
-      object_type    xml, target.object_type
-      verb           xml, target.verb
-      title          xml, target.title
-      link_alternate xml, TagManager.instance.url_for(target)
-    end
-
-    # Statuses have content and author
-    return unless target.is_a?(Status)
-
-    rich_content xml, target
-    verb         xml, target.verb
-    published_at xml, target.created_at
-    updated_at   xml, target.updated_at
-
-    author(xml) do
-      include_author xml, target.account
-    end
-
-    if target.reply?
-      in_reply_to xml, TagManager.instance.uri_for(target.thread), TagManager.instance.url_for(target.thread)
-    end
-
-    link_visibility xml, target
-
-    target.mentions.each do |mention|
-      link_mention xml, mention.account
-    end
-
-    target.media_attachments.each do |media|
-      link_enclosure xml, media
-    end
-
-    target.tags.each do |tag|
-      category xml, tag.name
-    end
-
-    category(xml, 'nsfw') if target.sensitive?
-    privacy_scope(xml, target.visibility)
-  end
-
-  def include_entry(xml, stream_entry)
-    unique_id      xml, stream_entry.created_at, stream_entry.activity_id, stream_entry.activity_type
-    published_at   xml, stream_entry.created_at
-    updated_at     xml, stream_entry.updated_at
-    title          xml, stream_entry.title
-    rich_content   xml, stream_entry.activity
-    verb           xml, stream_entry.verb
-    link_self      xml, account_stream_entry_url(stream_entry.account, stream_entry, format: 'atom')
-    link_alternate xml, account_stream_entry_url(stream_entry.account, stream_entry)
-    object_type    xml, stream_entry.object_type
-
-    # Comments need thread element
-    if stream_entry.threaded?
-      in_reply_to xml, TagManager.instance.uri_for(stream_entry.thread), TagManager.instance.url_for(stream_entry.thread)
-    end
-
-    if stream_entry.targeted?
-      target(xml) do
-        include_target(xml, stream_entry.target)
-      end
-    end
-
-    link_visibility xml, stream_entry.activity
-
-    stream_entry.mentions.each do |mentioned|
-      link_mention xml, mentioned
-    end
-
-    return unless stream_entry.activity.is_a?(Status)
-
-    stream_entry.activity.media_attachments.each do |media|
-      link_enclosure xml, media
-    end
-
-    stream_entry.activity.tags.each do |tag|
-      category xml, tag.name
-    end
-
-    category(xml, 'nsfw') if stream_entry.activity.sensitive?
-    privacy_scope(xml, stream_entry.activity.visibility)
-  end
-
-  private
-
-  def root_tag(xml, tag, &block)
-    xml.send(tag, {
-               'xmlns'          => TagManager::XMLNS,
-               'xmlns:thr'      => TagManager::THR_XMLNS,
-               'xmlns:activity' => TagManager::AS_XMLNS,
-               'xmlns:poco'     => TagManager::POCO_XMLNS,
-               'xmlns:media'    => TagManager::MEDIA_XMLNS,
-               'xmlns:ostatus'  => TagManager::OS_XMLNS,
-               'xmlns:mastodon' => TagManager::MTDN_XMLNS,
-             }, &block)
-  end
-
-  def single_link_avatar(xml, account, size, px)
-    xml.link('rel' => 'avatar', 'type' => account.avatar_content_type, 'media:width' => px, 'media:height' => px, 'href' => full_asset_url(account.avatar.url(size)))
-  end
-end
diff --git a/app/services/base_service.rb b/app/services/base_service.rb
index 6653255f2a3..99e8c875f4d 100644
--- a/app/services/base_service.rb
+++ b/app/services/base_service.rb
@@ -5,5 +5,4 @@ class BaseService
   include ActionView::Helpers::SanitizeHelper
 
   include RoutingHelper
-  include AtomBuilderHelper
 end
diff --git a/spec/helpers/atom_builder_helper_spec.rb b/spec/helpers/atom_builder_helper_spec.rb
deleted file mode 100644
index 0aca58ee7eb..00000000000
--- a/spec/helpers/atom_builder_helper_spec.rb
+++ /dev/null
@@ -1,187 +0,0 @@
-require 'rails_helper'
-
-RSpec.describe AtomBuilderHelper, type: :helper do
-  describe '#stream_updated_at' do
-    pending
-  end
-
-  describe '#entry' do
-    it 'creates an entry' do
-      expect(used_in_builder { |xml| helper.entry(xml) }).to match '<entry/>'
-    end
-  end
-
-  describe '#feed' do
-    it 'creates a feed' do
-      expect(used_in_builder { |xml| helper.feed(xml) }).to match '<feed xmlns="http://www.w3.org/2005/Atom" xmlns:thr="http://purl.org/syndication/thread/1.0" xmlns:activity="http://activitystrea.ms/spec/1.0/" xmlns:poco="http://portablecontacts.net/spec/1.0" xmlns:media="http://purl.org/syndication/atommedia" xmlns:ostatus="http://ostatus.org/schema/1.0" xmlns:mastodon="http://mastodon.social/schema/1.0"/>'
-    end
-  end
-
-  describe '#unique_id' do
-    it 'creates an id' do
-      time = Time.now
-      expect(used_in_builder { |xml| helper.unique_id(xml, time, 1, 'Status') }).to match "<id>#{TagManager.instance.unique_tag(time, 1, 'Status')}</id>"
-    end
-  end
-
-  describe '#simple_id' do
-    it 'creates an id' do
-      expect(used_in_builder { |xml| helper.simple_id(xml, 1) }).to match '<id>1</id>'
-    end
-  end
-
-  describe '#published_at' do
-    it 'creates a published tag' do
-      time = Time.now
-      expect(used_in_builder { |xml| helper.published_at(xml, time) }).to match "<published>#{time.iso8601}</published>"
-    end
-  end
-
-  describe '#updated_at' do
-    it 'creates an updated tag' do
-      time = Time.now
-      expect(used_in_builder { |xml| helper.updated_at(xml, time) }).to match "<updated>#{time.iso8601}</updated>"
-    end
-  end
-
-  describe '#verb' do
-    it 'creates an entry' do
-      expect(used_with_namespaces { |xml| helper.verb(xml, :post) }).to match '<activity:verb>http://activitystrea.ms/schema/1.0/post</activity:verb>'
-    end
-  end
-
-  describe '#content' do
-    it 'creates a content' do
-      expect(used_in_builder { |xml| helper.content(xml, 'foo') }).to match '<content type="html">foo</content>'
-    end
-  end
-
-  describe '#title' do
-    it 'creates a title' do
-      expect(used_in_builder { |xml| helper.title(xml, 'foo') }).to match '<title>foo</title>'
-    end
-  end
-
-  describe '#author' do
-    it 'creates an author' do
-      expect(used_in_builder { |xml| helper.author(xml) }).to match '<author/>'
-    end
-  end
-
-  describe '#target' do
-    it 'creates a target' do
-      expect(used_with_namespaces { |xml| helper.target(xml) }).to match '<activity:object/>'
-    end
-  end
-
-  describe '#object_type' do
-    it 'creates an object type' do
-      expect(used_with_namespaces { |xml| helper.object_type(xml, :person) }).to match '<activity:object-type>http://activitystrea.ms/schema/1.0/person</activity:object-type>'
-    end
-  end
-
-  describe '#uri' do
-    it 'creates a uri' do
-      expect(used_in_builder { |xml| helper.uri(xml, 1) }).to match '<uri>1</uri>'
-    end
-  end
-
-  describe '#name' do
-    it 'creates a name' do
-      expect(used_in_builder { |xml| helper.name(xml, 1) }).to match '<name>1</name>'
-    end
-  end
-
-  describe '#summary' do
-    it 'creates a summary' do
-      expect(used_in_builder { |xml| helper.summary(xml, 1) }).to match '<summary>1</summary>'
-    end
-  end
-
-  describe '#subtitle' do
-    it 'creates a subtitle' do
-      expect(used_in_builder { |xml| helper.subtitle(xml, 1) }).to match '<subtitle>1</subtitle>'
-    end
-  end
-
-  describe '#link_alternate' do
-    it 'creates a link' do
-      expect(used_in_builder { |xml| helper.link_alternate(xml, 1) }).to match '<link rel="alternate" type="text/html" href="1"/>'
-    end
-  end
-
-  describe '#link_self' do
-    it 'creates a link' do
-      expect(used_in_builder { |xml| helper.link_self(xml, 1) }).to match '<link rel="self" type="application/atom+xml" href="1"/>'
-    end
-  end
-
-  describe '#link_hub' do
-    it 'creates a link' do
-      expect(used_in_builder { |xml| helper.link_hub(xml, 1) }).to match '<link rel="hub" href="1"/>'
-    end
-  end
-
-  describe '#link_salmon' do
-    it 'creates a link' do
-      expect(used_in_builder { |xml| helper.link_salmon(xml, 1) }).to match '<link rel="salmon" href="1"/>'
-    end
-  end
-
-  describe '#portable_contact' do
-    let(:account) { Fabricate(:account, username: 'alice', display_name: 'Alice in Wonderland') }
-
-    it 'creates portable contacts entries' do
-      expect(used_with_namespaces { |xml| helper.portable_contact(xml, account) }).to match '<poco:displayName>Alice in Wonderland</poco:displayName>'
-    end
-  end
-
-  describe '#in_reply_to' do
-    it 'creates a thread' do
-      expect(used_with_namespaces { |xml| helper.in_reply_to(xml, 'uri', 'url') }).to match '<thr:in-reply-to ref="uri" href="url" type="text/html"/>'
-    end
-  end
-
-  describe '#link_mention' do
-    let(:account) { Fabricate(:account, username: 'alice') }
-
-    it 'creates a link' do
-      expect(used_in_builder { |xml| helper.link_mention(xml, account) }).to match '<link rel="mentioned" href="https://cb6e6126.ngrok.io/users/alice" ostatus:object-type="http://activitystrea.ms/schema/1.0/person"/>'
-    end
-  end
-
-  describe '#include_author' do
-    pending
-  end
-
-  describe '#include_entry' do
-    pending
-  end
-
-  describe '#link_avatar' do
-    let(:account) { Fabricate(:account, username: 'alice') }
-
-    it 'creates a link' do
-      expect(used_with_namespaces { |xml| helper.link_avatar(xml, account) }).to match '<link rel="avatar" type="" media:width="120" media:height="120" href="http://test.host/avatars/original/missing.png"/>'
-    end
-  end
-
-  describe '#link_enclosure' do
-    pending
-  end
-
-  describe '#logo' do
-    it 'creates a logo' do
-      expect(used_in_builder { |xml| helper.logo(xml, 1) }).to match '<logo>1</logo>'
-    end
-  end
-
-  def used_in_builder(&block)
-    builder = Nokogiri::XML::Builder.new(&block)
-    builder.doc.root.to_xml
-  end
-
-  def used_with_namespaces(&block)
-    used_in_builder { |xml| helper.entry(xml, true, &block) }
-  end
-end