Tailwind CSS v4 support

[justalever]

Running rails new my_app -c tailwind results in the following for me (rails 8.0.1 / ruby 3.4.1):

Add build:css script
  Add build:css script
         run    npm pkg set scripts.build:css="tailwindcss -i ./app/assets/stylesheets/application.tailwind.css -o ./app/assets/builds/application.css --minify" from "."
         run    yarn build:css from "."
yarn run v1.22.22
$ tailwindcss -i ./app/assets/stylesheets/application.tailwind.css -o ./app/assets/builds/application.css --minify
rbenv: tailwindcss: command not found

The `tailwindcss' command exists in these Ruby versions:
  3.3.3

error Command failed with exit code 127.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
         run  bundle install --quiet
         run  bundle binstubs kamal
         run  bundle exec kamal init
Created configuration file in config/deploy.yml
Created .kamal/secrets file
Created sample hooks in .kamal/hooks
       force  .kamal/secrets
       force  config/deploy.yml
       rails  solid_cache:install solid_queue:install solid_cable:install
      create  config/cache.yml
      create  db/cache_schema.rb
        gsub  config/environments/production.rb
      create  config/queue.yml
      create  config/recurring.yml
      create  db/queue_schema.rb
      create  bin/jobs
        gsub  config/environments/production.rb
      create  db/cable_schema.rb
       force  config/cable.yml

It looks like there are a few things to update to get full v4 support:

• Ditch the tailwind.config.js file
• Update build:css script and dependencies (unsure if it should be the Tailwind CLI or PostCSS?)
• update @import statements in application.tailwind.css

[BarnabeD]

Yesterday I upgraded my rails app which is running on rails main.
I had several issues with yarn in local + in kamal deployment

I solved everything by adding simply add the two gems in my gem file.

gem "tailwindcss-ruby"
gem "tailwindcss-rails"