diff --git a/.dockerignore b/.dockerignore
index de0577641..3357e5b8d 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -2,3 +2,4 @@
 .env.*
 public/system
 public/assets
+node_modules
diff --git a/Dockerfile b/Dockerfile
index bb4c70d87..2b15d437b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,15 +2,17 @@ FROM ruby:2.2.4
 
 ENV RAILS_ENV=production
 
-RUN apt-get update -qq && apt-get install -y build-essential libpq-dev && rm -rf /var/lib/apt/lists/*
+RUN apt-get update -qq && apt-get install -y build-essential libpq-dev libxml2-dev libxslt1-dev nodejs nodejs-legacy npm && rm -rf /var/lib/apt/lists/*
 RUN mkdir /mastodon
 
 WORKDIR /mastodon
 
 ADD Gemfile /mastodon/Gemfile
 ADD Gemfile.lock /mastodon/Gemfile.lock
+ADD package.json /mastodon/package.json
 
-RUN bundle install --deployment --without test --without development
+RUN bundle install --deployment --without test development
+RUN npm install
 
 ADD . /mastodon
 
diff --git a/app/assets/javascripts/cable.js b/app/assets/javascripts/cable.js
index 71ee1e66d..03258761c 100644
--- a/app/assets/javascripts/cable.js
+++ b/app/assets/javascripts/cable.js
@@ -3,7 +3,6 @@
 //
 //= require action_cable
 //= require_self
-//= require_tree ./channels
 
 (function() {
   this.App || (this.App = {});