csspin-rails

Pin CSS packages from npm into a Rails app's vendor/assets/stylesheets — without Node.js.

Works like importmap-rails, but for CSS. Packages are fetched from jsDelivr.

Installation

Add to your Gemfile:

gem "csspin-rails"

Then run:

bundle install

Usage

# Pin a package (latest version)
bundle exec csspin pin sourdough-toast

# Pin a specific version
  bundle exec csspin pin sourdough-toast@2.0.7

# Pin a scoped package
bundle exec csspin pin @37signals/lexxy

CSS is saved to vendor/assets/stylesheets/<package>.css.

If you want bin/csspin, run bundle binstubs csspin-rails first.

After pinning, the CLI prints integration snippets:

Sprockets snippet: *= require sourdough-toast
Sass snippet: @import "sourdough-toast";

CLI

Usage: csspin pin <package|package@version>

Commands:
  pin <package|package@version>  Download a CSS package into vendor/assets/stylesheets

Options:
  -v, --version  Show version
  -h, --help     Show this help

How it works

1. Parses the package name and optional version
2. Resolves candidate URLs on jsDelivr (/dist/<pkg>.css, then the bare package URL)
3. Downloads the first successful CSS response (follows redirects, validates content-type)
4. Writes the file to vendor/assets/stylesheets/

Development

bundle install
bundle exec standardrb
bundle exec rake test

Releasing

This repo publishes via GitHub Actions when you push a tag matching v* (see .github/workflows/release.yml).

1. Update lib/csspin/version.rb
2. Run bundle exec rake test (and any linting you want)
3. Commit
4. Tag: git tag vX.Y.Z
5. Push commit: git push origin HEAD
6. Push tag: git push origin vX.Y.Z

License

The gem is available as open source under the terms of the MIT License.