Import Maps

Rails uses import maps for JavaScript by default. This allows you to write modern JavaScript modules with no build steps.

You can find the JavaScript pins in config/importmap.rb. This file maps the JavaScript package names with the source file which is used to generate the importmap tag in the browser.

# Pin npm packages by running ./bin/importmap

pin "application"
pin "@hotwired/turbo-rails", to: "turbo.min.js"
pin "@hotwired/stimulus", to: "stimulus.min.js"
pin "@hotwired/stimulus-loading", to: "stimulus-loading.js"
pin_all_from "app/javascript/controllers", under: "controllers"
pin "trix"
pin "@rails/actiontext", to: "actiontext.esm.js"

Import maps keep the setup clean and minimal, while still supporting modern JavaScript features.

What are these JavaScript files already in our import map? They are a frontend framework called Hotwire that Rails uses by default.