Install following packages with yarn yarn add bootstrap yarn add @popperjs/core Next, we need to import bootstraps to our application.js import "bootstrap" import "../stylesheets/application" Import bootstrap css to - app/javascript/stylesheets/application.scss @import '~bootstrap/scss/bootstrap'; Next add following to app/views/layouts/application.html.erb <%= stylesheet_pack_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %> Now add following config/webpack/environment.js const webpack = require('webpack') environment.plugins.append('Provide', new webpack.ProvidePlugin({ Popper: ['@popperjs/core', 'default'] }))