# Installing DEV on Linux

## Installing prerequisites

_These prerequisites assume you're working on a Linux-based operating system, but they have only been tested on Ubuntu 18.04._

### Ruby

1. If you don't already have a Ruby version manager, we highly recommend [rbenv](https://github.com/rbenv/rbenv). Please follow their [installation guide](https://github.com/rbenv/rbenv#installation).
1. With the Ruby version manager, install the Ruby version listed on our badge. (ie with rbenv: `rbenv install 2.6.5`)

For very detailed rbenv installation directions on several distros, please visit [DigitalOcean's guide](https://www.digitalocean.com/community/tutorials/how-to-install-ruby-on-rails-with-rbenv-on-ubuntu-18-04).

### Yarn

There are two ways to install Yarn.

- Yarn's official [installation guide](https://yarnpkg.com/en/docs/install#debian-stable) (recommended).
- [DigitalOcean's detailed tutorial](https://www.digitalocean.com/community/tutorials/how-to-install-node-js-on-ubuntu-18-04) describes how to install [Node version Manager](https://github.com/creationix/nvm). By installing NVM you can select a Node version (we recommend either LTS or current); the guide will also explain how to install NPM. This way you'll have Node, NPM, and then you can run `npm install -g yarn` to install Yarn.

### PostgreSQL

1. Run `sudo apt update && sudo apt install postgresql postgresql-contrib libpq-dev`.
1. To test the installation you can run `sudo -u postgres psql` which should open a PostgreSQL prompt. Exit the prompt by running `\q` then run `sudo -u postgres createuser -s $YOUR_USERNAME` where `$YOUR_USERNAME` is the username you are currently logged in as.

There are more than one ways to setup PostgreSQL. For additional configuration, check out our [PostgreSQL setup guide](/installation/postgresql) or the official [PostgreSQL](https://www.postgresql.org/) site for further information.

### ImageMagick

DEV uses [ImageMagick](https://imagemagick.org/) to manipulate images on upload.

Please refer to ImageMagick's [instructions](https://imagemagick.org/script/download.php) on how to install it.

## Installing DEV

1. Fork DEV's repository, e.g. <https://github.com/thepracticaldev/dev.to/fork>
1. Clone your forked repository, e.g. `git clone https://github.com/<your-username>/dev.to.git`
1. Install bundler with `gem install bundler`
1. Set up your environment variables/secrets

   - Take a look at `Envfile`. This file lists all the `ENV` variables we use and provides a fake default for any missing keys. You'll need to get your own free [Algolia credentials](/backend/algolia) to get your development environment running.
   - The [backend guide](/backend) will show you how to get free API keys for additional services that may be required to run certain parts of the app.
   - For any key that you wish to enter/replace:

     1. Create `config/application.yml` by copying from the provided template (i.e. with bash: `cp config/sample_application.yml config/application.yml`). This is a personal file that is ignored in git.
     1. Obtain the development variable and apply the key you wish to enter/replace. i.e.:

     ```shell
     GITHUB_KEY: "SOME_REAL_SECURE_KEY_HERE"
     GITHUB_SECRET: "ANOTHER_REAL_SECURE_KEY_HERE"
     ```

   - If you are missing `ENV` variables on bootup, the [envied](https://rubygems.org/gems/envied) gem will alert you with messages similar to `'error_on_missing_variables!': The following environment variables should be set: A_MISSING_KEY.`.
   - You do not need "real" keys for basic development. Some features require certain keys, so you may be able to add them as you go.

1. Run `bin/setup`

### Possible error messages

While installing, you might run into an error due to the `pg` gem requiring PostgreSQL libraries. If so, please run `sudo apt-get install libpq-dev` before retrying.

While installing, you might run into an error due to the `sass-rails` gem requiring `sassc`, which requires the `g++` compiler. If so, please run `sudo apt-get install g++` before retrying.

While installing, if you didn't install `node` or `nvm` manually, you might run into an error due to an older system node version being present, which can cause issues while `yarn` is installing packages. If so, you'll need to [install `nvm`](https://github.com/nvm-sh/nvm#installation-and-update) and then run `nvm install node` to get the most recent node version before retrying.