How to set-up a Ruby and Elixir dev environment on macOS (2021)

This is the latest version of my dev env set-up guide, perfect for use after getting a new machine or carrying out a fresh install of macOS. You can use this guide for similar web development set-ups too, since the version manager we’ll be using (asdf) is perfect for a large number of different languages.

If you don’t need Ruby or don’t need 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 the following in terminal – be sure to start Xcode afterwards so you can agree to their terms:

Homebrew

In the terminal copy and paste the following:

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 add the following to your ~/.zshrc file:

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/libexec/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 2.7.2 and 3.0.0 with which versions 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:

If you would prefer docs weren’t installed, add this to your ‘.gemrc’ file (create one if it doesn’t exist):

For Rails:

Open a new terminal window 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

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

If you want to use Janus, it 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 highly recommend btw!!