How To Install Rails and Create a New Rails App on a Mac, in 5 Steps!

In my guide to installing Ruby gems on a Mac, I wrote about how hard it is for pretty much anyone new to Ruby to install gems on a Mac, and how my script makes it easy. Even for experienced folks, using a script saves so much time when setting up a new computer. I recently made some new improvements that make it even easier to create a Rails app. Doing everything manually would involve at least 15 steps.

With the latest updates, creating a new Rails app only takes 5 steps:

   mkdir ~/testing-rails && cd ~/testing-rails
   chruby 2.7.4
   rails new .

That’s it! Once it’s done creating the app (it takes a few minutes), you can then run the app:

rails s

and view it in your browser at http://localhost:3000.

To make sure the correct Ruby version is used whenever you cd into your Rails app, add a .ruby-version file:

echo 'ruby-2.7.4' >> .ruby-version

Finally, capture all of these new files in a git commit:

git add .
git commit -m "Create new Rails app with rails new"

Now you can start coding your app, but first read about the first gem you should add to your Rails app.