We only support Docker based installs now. Please see [our **official install guide**](https://github.com/discourse/discourse/blob/master/docs/INSTALL.md) for supported install instructions.
This guide takes you through the steps for deploying Discourse to the [Heroku](http://www.heroku.com/) cloud application platform. If you're unfamiliar with Heroku, [read this first](https://devcenter.heroku.com/articles/quickstart). The basic deployment of Discourse requires several services that will cost you money. In addition to the [750 free Dyno hours](https://devcenter.heroku.com/articles/usage-and-billing) provided by Heroku, the application requires one additional process to be running for the Sidekiq queue ($34 monthly), and a Redis database plan that supports a minimum of 2 databases (average $10 monthly).
There are two options for precompilation. Either precompile locally, **before each deploy** or enable [Heroku's experimental user-env-compile](https://devcenter.heroku.com/articles/labs-user-env-compile) feature and Heroku will precompile your assets for you.
**Notice:** We don't use Foreman to start precompilation, as this would precompile in the development environment. Instead, rake assets:precompile runs in the production environment by default, as it should.
4. In Discourse admin settings, set `force_hostname` to your applications Heroku domain.
This step is required for Discourse to properly form links sent with account confirmation emails and password resets. The auto detected application url would point to an Amazon AWS instance.
In the [Heroku dashboard](https://dashboard.heroku.com/apps), select your app and you will see the separate processes that have been created for your application under Resources. You will only need to start the sidekiq process for your application to run properly. The worker process has been generated as a Rails default and can be ignored. As you can see **the Sidekiq process costs $34 monthly** to run. If you want to reduce this cost, check out [Advanced Heroku deployment](#advanced-heroku-deployment).
##### Your Discourse application should now be functional. However, you will still need to [configure mail](#email) functionality and file storage for uploaded images. For some examples of doing this within Heroku, see [Heroku add-on examples](#heroku-add-on-examples).
Using Foreman to start the application allows you to mimic the way the application is started on Heroku. It loads environment variables via the .env file and instantiates the application using the Procfile. In the .env sample file, we have set `RAILS_ENV='development'`, this makes the Rails environment variable available globally, and is required when starting this application using Foreman.
1. Add the [Mandrill by MailChimp](https://devcenter.heroku.com/articles/mandrill) add-on from the [Heroku add-ons](https://addons.heroku.com/) page, or install from the command line using:
heroku addons:add mandrill:starter
2. Configure the smtp settings in the production environment config file.
@adamloving: I think there is still a file size issue. I was testing with a 2MB file that wasn't big enough to trigger the "file too big" Discourse error message, but didn't make it to S3 either.
1. Add the [Blitz](https://addons.heroku.com/blitz) add-on from the [Heroku add-ons](https://addons.heroku.com/) page, or install from the command line using:
You can now run basic load tests against your instalation. Here's an example query with the rush of users scaling from 1 to 250 over 60 seconds. The timeout (-T) is set to 30 seconds, as after this Heroku will kill a process and return an error anyway.
1. Add the [loader.io](https://addons.heroku.com/loaderio) add-on from the [Heroku add-ons](https://addons.heroku.com/) page, or install from the command line using:
loader.io is still in beta, so you mileage may vary, but the tests are free for now.
They currently require you verify your domain. A simple way to do this is to add a hard coded static route to `config.routes.rb` using the loaderio verification key. You'll see the key the first time you try to run a load test.
Adding the [Autoscaler Gem](https://github.com/JustinLove/autoscaler) can help you better manage the running cost of your application by scaling down the Sidekiq worker process when not in use. This could save up to $34 per month depending on your usage levels.
##### Whilst this Gem has the potential to save you money, it in no way guarantees it. Use of this Gem should be combined with careful monitoring of your applications processes and usage alerts where necessary.
1. Push your Heroku API key and app name to Heroku.
Heroku Cedar stack does not support Nginx as a caching layer, so you may want to host your static assets in a CDN so you're not hitting your rails app for every asset request.
This can be done simply using the [Asset Sync](https://github.com/rumblelabs/asset_sync) gem.
You'll need an Amazon S3 account set up with a bucket configured with your app name (appname-assets), and a separate user with write access to that bucket. You can create the new user in Account > Security Credentials. See [AWS best practices](http://docs.aws.amazon.com/IAM/latest/UserGuide/IAMBestPractices.html) for more details.
**Caveat:** This example relies on the app being deployed using the `heroku labs:enable user-env-compile` method detailed above. For instructions on manual compilation, please refer to the [Asset Sync](https://github.com/rumblelabs/asset_sync) gem readme.
If you open Chrome's Inspector, click on Network and refresh the page, your assets should now be showing an amazonaws.com url. Please refer to the [Asset Sync](https://github.com/rumblelabs/asset_sync) gem readme for more configuration options, or to use another CDN such as AWS CloudFront for better performance.