Shadwire ports the shadcn/ui Open Code model to Ruby on Rails.

The source of truth is registry/. The Rails app in sandbox/ consumes copied registry files so components are validated in a real Rails, ViewComponent, Tailwind CSS v4, and Hotwire environment.

58 components, listed with shadwire list. Search by what you need (shadwire search form), then read a component API with shadwire info button.

Helpers use the ui_* prefix.

<%= render Ui::ButtonComponent.new(variant: :outline, size: :sm) do %>
  Save
<% end %>

<%= ui_button(variant: :outline, size: :sm) { "Save" } %>

Icons are rendered with lucide-rails (add gem "lucide-rails" to the consuming app). Compose them inside other components:

<%= ui_button { (ui_icon("download") + " Download").html_safe } %>
<%= ui_button(size: :icon) { ui_icon("plus", label: "Add item") } %>

Shadwire ships a shadwire CLI (packages/cli/) that installs component source into a Rails app and keeps it in sync with the registry — the shadcn Open Code flow. Installed files are yours; there is no runtime dependency on Shadwire.

Install it globally, or add it to the consuming app directly:

gem install shadwire                       # global — bootstrap with `shadwire init`
bundle add shadwire --group development    # in the app — bootstrap with `bundle exec shadwire init`

Bootstrap once. init adds shadwire to the app's development group (if it is not there already) and writes the bin/shadwire binstub. That binstub is how you run the CLI from then on — one entry point, pinned to the app's bundle:

shadwire init                     # writes shadwire.json + base files + bin/shadwire
bin/shadwire add button dialog    # installs components and their registry dependencies
bin/shadwire list                 # every component in the registry catalog

init is the one command you run un-prefixed, because it is what creates the binstub. Use bundle exec shadwire init when the gem is in the Gemfile rather than installed globally.

Components install from the hosted registry (https://shadwire.edumoraes.dev.br/r) by default; override with --registry (an https:// URL or a local file:// path).

Agents / CI — every command runs non-interactively with --yes, emits machine-readable output with --json, and can target another app with --cwd. bin/shadwire status --json reports the whole install in one call, and bin/shadwire diff --exit-code exits non-zero when an installed file has drifted from the registry, so CI can fail on drift. See packages/cli/README.md for the full command reference.

Coding agents — Claude Code, Codex, Cursor, OpenCode and ~20 others — can install the Shadwire skill for full context on the CLI and components:

npx skills add edumoraes/shadwire

The skill lives in skills/shadwire/. It carries workflow and conventions, not data: component names, variants, props and helper names are pulled at runtime from bin/shadwire status --json and bin/shadwire info --json, so it always reflects what is actually installed. CI verifies that everything the skill names still exists.

The skill's allowed-tools grant covers only the turn that invokes it, so it stops the permission prompts for that turn and no longer. To silence them for good, add an allow rule to the consuming app's .claude/settings.json:

{ "permissions": { "allow": ["Bash(bin/shadwire *)"] } }

Agents that cannot install the skill can read the same catalog as plain text:

• /r/llms.txt — every component with when to use it
• /r/llms-full.txt — every component's full API and usage

Edit source files in registry/rails/ui.

Sync registry files into the sandbox:

bin/sync_registry

Run all tests:

rake test

Run sandbox tests only:

cd sandbox
bin/rails test test/components test/integration/ui_accessibility_test.rb

Theme tokens live in registry/rails/ui/styles/shadwire.css under :root and .dark. Tailwind v4 reads them through @theme inline, so component classes should use semantic utilities such as bg-primary, text-muted-foreground, border-input, and ring-ring instead of hardcoded colors.

Use Conventional Commits:

git commit -m "feat: add button component"
git commit -m "test: cover card component"
git commit -m "docs: update registry workflow"