How to set-up a Ruby and Elixir dev environment on macOS Catalina

Edit: Please note there is a newer version of this guide here: https://astonj.com/how-to-set-up-a-ruby-and-elixir-dev-environment-on-macos-2021/

Having recently started afresh on macOS, I thought I’d make some notes on setting up a new dev environment. In this post we’ll set up a fresh dev environment for Ruby and Elixir – but you can use this guide for any similar web development set-up since the version manager we’ll be using (asdf) can be used for lots and lots and lots of different languages.

If you don’t need Ruby or Elixir, you can just omit those steps. We’ll also add a few other common web development tools or packages. In short, we’ll be covering installation of:

• Xcode
• Command line tools
• Homebrew
• ImageMagic
• Git
• Postgres
• TextMate
• MacVim
• Asdf
• Ruby
• Rubygems
• Rails
• Erlang
• Elixir
• Hex
• Phoenix

Xcode

Simply download and install Xcode from the App store.

Command Line Tools

Once Xcode has installed, open it, then go to preferences > downloads, and install command line tools. Or alternatively, enter this in terminal:

Homebrew

In the terminal copy and paste the following:

In your .zshrc file add:

Let’s get brewing – and install Postgres, ImageMagick and git

Let’s update Homebrew first:

Postgres

Then:

Then to start Postgres and on startup, run:

Then create your initial db:

Then:

That will create your Postgres user (use CTRL Z to exit).

Git and ImageMagick

Then in terminal:

Installing asdf

In terminal, type:

Then in terminal run:

This will add the following to the bottom of your ~/.zshrc file:

Installing asdf plugin dependencies

In terminal:

If you need to upgrade asdf, use brew upgrade asdf.

How to remove asdf

If you ever need to remove asdf, you can do so pretty easily:

• In your .zshrc remove the line that was added on installation:. /usr/local/opt/asdf/asdf.sh
• Run rm -rf ~/.asdf/ ~/.tool-versions to completely remove all the asdf files from your system.
• In terminal: brew uninstall --force asdf

Installing Ruby

Skip if you don’t need Ruby and Rails…

In terminal:

To see which versions are available:

Then install the versions you want with the following, just replace 2.6.5 with the version you need:

Then set your preferred defaults with:

And to use a specific version in any particular directory:

To add new Rubies:

Or simply:

Rubygems and Rails

Open a fresh terminal window and:

For Rails:

Restart terminal and check your versions by:

Installing Elixir & Erlang

Skip if you don’t need Elixir and Phoenix

In terminal:

To see which versions are available:

Then install the versions you want with the following, just replace version numbers with whichever versions you need:

And to use a specific version in any particular directory:

Installing Hex and Phoenix

Phoenix uses Brunch.io which relies on npm, the Node.js package manager, so lets install that as well via asdf:

To install Phoenix:

Finally, check your versions by:

Doesn’t that feel good? Now you can install your favourite code editors!

Code Editors

I’m going to install two here, TextMate and MacVim 😀

TextMate 2

Download from here: https://macromates.com/download

Download my Elixify theme and follow the instructions from here (but you just need to double click on the TextMate 2 theme called Elixify.tmbundle)

Install Elixir Bundle:

MacVim

Next you’ll want to use Janus, which can be installed by running this in terminal:

In it paste:

Then in terminal, to give it some breathing space at the top do:

To install the Elixify theme download from here and follow the instructions for MacVim.

That’s it – you now have a fully working dev environment for Ruby, Elixir, Erlang, Node and any other language you want to add via the numerous supported by asdf… which I am really loving btw!!