TailwindCSS JIT without Webpacker

A simple vanilla PostCSS build setup for TailwindCSS JIT
Icons/chart bar
Used 40 times
Created by
D Dom Christie

You'll need to have a recent version of Node.js. (This template assumes that the Rails project does not have a package.json with "build" and "start" fields.)

Once the template has installed, run the following alongside rails s:
npm start

This will monitor your templates and build a minimal Tailwind file for consumption by the asset pipeline.

For deployment to Heroku, check out this guide.

Run this command in your Rails app directory in the terminal:

rails app:template LOCATION="https://railsbytes.com/script/Vwysmv"
Template Source

Review the code before running this template on your machine.

run "npm init -y"
run "npm install -D tailwindcss@latest postcss@latest autoprefixer@latest"
run "npx tailwindcss init"

run "touch app/assets/stylesheets/tailwind.css"
inject_into_file "app/assets/stylesheets/tailwind.css" do <<~EOF
@tailwind base;
@tailwind components;
@tailwind utilities;

inject_into_file "tailwind.config.js", after: "module.exports = {" do <<-MODE.chomp

  mode: 'jit',

gsub_file "tailwind.config.js", /^\s+purge:\s\[\],/, <<-PURGE.chomp
  purge: [

inject_into_file "package.json", after: "\"scripts\": {" do <<-SCRIPTS.chomp

    "build": "tailwindcss -i ./app/assets/stylesheets/tailwind.css -o ./app/assets/stylesheets/tailwind-build.css",
    "start": "tailwindcss -i ./app/assets/stylesheets/tailwind.css -o ./app/assets/stylesheets/tailwind-build.css --watch",

inject_into_file "app/assets/stylesheets/application.css", after: "require_tree ." do <<-STYLES.chomp

 *= stub tailwind
 *= require tailwind-build
Julian Rubisch
Hi Dom!

Love this and use it quite extensively... however, today I added @tailwindcss/forms, after which npm required me to install lilconfig and tmp ("module not found").

And now JIT is no longer working. It does compile the styles, but only after restarting npm start.

I looked for similar issues on the issue tracker but couldn't find any. Do you know what could be wrong by any chance?

Julian Rubisch
Addendum: seems like updating all postcss postcss-cli tailwindcss autoprefixer to latest has removed some incompatibility!
Dom Christie
Hey Julian! Glad to hear you're enjoying this (before the issues :)

The Tailwind v2.2 upgrade broke some compatibility when building via the default postcss-cli script. This also confused me for a while but is noted here: https://tailwindcss.com/docs/just-in-time-mode#styles-don-t-update-when-saving-content-files

I have updated the RailsByte to use the new Tailwind CLI, which seems to fix the JIT updating issue. I've not used @tailwindcss/forms so I'm not sure what the issue might be there :/