Railgun by Cloudflare
With Cloudflare's Railgun you can decrease your Heroku app’s load time across the world by 2-3 times.
Prerequisites
Railgun is only available on Business plan.
We assume your Heroku app is already configured to use CloudFlare DNS and CDN features.
You'll need a Railgun Activation Key. Copy it from your CloudFlare Account Settings
and assign to RAILGUN_ACTIVATION_KEY
Heroku config variable
heroku config:set RAILGUN_ACTIVATION_KEY=xxxxxxxxx
Running the stack
heroku addons:create dockhero
heroku plugins:install dockhero
heroku dh:generate railgun # this generates dockhero-compose.yml
heroku dh:compose up -d
Now turn on Railgun for your entire Cloudflare domain. Click “Test” button to make sure everything works.
That's it. Try sending requests to your app via CloudFlare domain name.
Cf-Railgun
HTTP header should appear on all of the responses from your app.