diff --git a/app/controllers/bootstrap_controller.rb b/app/controllers/bootstrap_controller.rb
new file mode 100644
index 0000000000..dca7007c58
--- /dev/null
+++ b/app/controllers/bootstrap_controller.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+class BootstrapController < ApplicationController
+  include ApplicationHelper
+  include ActionView::Helpers::AssetUrlHelper
+
+  # This endpoint allows us to produce the data required to start up Discourse via JSON API,
+  # so that you don't have to scrape the HTML for `data-*` payloads
+  def index
+    locale = script_asset_path("locales/#{I18n.locale}")
+
+    preload_anonymous_data
+    if current_user
+      current_user.sync_notification_channel_position
+      preload_current_user_data
+    end
+
+    bootstrap = {
+      theme_ids: theme_ids,
+      title: SiteSetting.title,
+      current_homepage: current_homepage,
+      locale_script: "#{Discourse.base_url}#{locale}",
+      setup_data: client_side_setup_data,
+      preloaded: @preloaded
+    }
+
+    render_json_dump(bootstrap: bootstrap)
+  end
+end
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 482b2477d3..f6bda658a3 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -356,6 +356,7 @@ module ApplicationHelper
   end
 
   def loading_admin?
+    return false unless defined?(controller)
     controller.class.name.split("::").first == "Admin"
   end
 
diff --git a/config/routes.rb b/config/routes.rb
index 69ade71938..e763252bc6 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -14,6 +14,8 @@ Discourse::Application.routes.draw do
   match "/404", to: "exceptions#not_found", via: [:get, :post]
   get "/404-body" => "exceptions#not_found_body"
 
+  get "/bootstrap" => "bootstrap#index"
+
   post "webhooks/aws" => "webhooks#aws"
   post "webhooks/mailgun"  => "webhooks#mailgun"
   post "webhooks/mailjet"  => "webhooks#mailjet"
diff --git a/spec/requests/bootstrap_controller_spec.rb b/spec/requests/bootstrap_controller_spec.rb
new file mode 100644
index 0000000000..6495eb4d28
--- /dev/null
+++ b/spec/requests/bootstrap_controller_spec.rb
@@ -0,0 +1,40 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+describe BootstrapController do
+
+  it "returns data as anonymous" do
+    get "/bootstrap.json"
+    expect(response.status).to eq(200)
+
+    json = response.parsed_body
+    expect(json).to be_present
+
+    bootstrap = json['bootstrap']
+    expect(bootstrap).to be_present
+    expect(bootstrap['title']).to be_present
+    expect(bootstrap['setup_data']['base_url']).to eq(Discourse.base_url)
+    preloaded = bootstrap['preloaded']
+    expect(preloaded['site']).to be_present
+    expect(preloaded['siteSettings']).to be_present
+    expect(preloaded['currentUser']).to be_blank
+    expect(preloaded['topicTrackingStates']).to be_blank
+  end
+
+  it "returns user data when authenticated" do
+    user = Fabricate(:user)
+    sign_in(user)
+    get "/bootstrap.json"
+    expect(response.status).to eq(200)
+
+    json = response.parsed_body
+    expect(json).to be_present
+
+    bootstrap = json['bootstrap']
+    preloaded = bootstrap['preloaded']
+    expect(preloaded['currentUser']).to be_present
+    expect(preloaded['topicTrackingStates']).to be_present
+  end
+
+end