web_ruby_ui 💎🌐

The 100% Pure Ruby Frontend Web Framework in WebAssembly.

Build interactive Single-Page Applications (SPAs) entirely in Ruby running inside the browser via ruby.wasm — Zero JavaScript, Zero React, Zero Node, and Zero NPM dependencies.

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Key Features 🚀

• ⚡ 100% Pure Ruby Frontend: Write interactive web components, event listeners, and state management in native Ruby.
• 🔄 Reactive State Management: Define state :count, default: 0. Updating state (self.count += 1) automatically re-renders component views.
• 🌳 Virtual DOM Diffing: In-memory VNode tree generation and diffing engine for optimal browser DOM rendering.
• 🗺️ Client-Side SPA Routing: Single-page application route matching (Router) for multi-view Ruby web apps.
• 🛠️ Dev Server & CLI Tooling: web_ruby_ui dev launches a local WebAssembly dev server with instant browser hot-loading.

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Architecture Overview 📐

┌─────────────────────────────────────────────────────────────┐
  BROWSER (WebAssembly Environment)
  ┌─────────────────────────────────────────────────────────┐
    JS::Object (Browser DOM APIs)
         ▲
         │ DOM Events (onclick, oninput) & Render Patches
         ▼
    WebRubyUI::DOM (Event Bridge & JS Interop)
         ▲
         │ In-Memory VNode Tree & Patch Diffing
         ▼
    WebRubyUI::Component (Reactive State & HTML DSL)
  └─────────────────────────────────────────────────────────┘
└─────────────────────────────────────────────────────────────┘

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Installation

Add this line to your application's Gemfile:

gem 'web_ruby_ui'

And then execute:

bundle install

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Quickstart (Todo App in Pure Ruby)

Create a reactive Single-Page Application without touching JavaScript:

require 'web_ruby_ui'

class TodoApp < WebRubyUI::Component
  state :items, default: [
    { id: 1, title: 'Learn Ruby WebAssembly', completed: true },
    { id: 2, title: 'Build WebRubyUI frontend framework', completed: true }
  ]
  state :new_title, default: ''

  def render
    div(class: 'max-w-md mx-auto my-10 p-6 bg-white rounded-xl shadow-lg') do
      h1(class: 'text-2xl font-bold text-indigo-600 mb-4') { 'RubyWasm Todo App 💎' }

      # Add Todo Form
      div(class: 'flex mb-4 gap-2') do
        input(
          type: 'text',
          class: 'flex-1 px-4 py-2 border rounded-lg',
          placeholder: 'What needs to be done?',
          value: new_title,
          oninput: ->(e) { self.new_title = e[:target][:value] }
        )
        button(
          class: 'px-4 py-2 bg-indigo-600 text-white rounded-lg font-semibold',
          onclick: -> { add_todo }
        ) { 'Add' }
      end

      # Todo List
      ul(class: 'divide-y divide-gray-200') do
        items.each do |item|
          li(class: 'py-3 flex items-center justify-between') do
            span(class: item[:completed] ? 'line-through text-gray-400' : 'text-gray-800') do
              item[:title]
            end
          end
        end
      end
    end
  end

  private

  def add_todo
    return if new_title.nil? || new_title.strip.empty?
    self.items = items + [{ id: Time.now.to_i, title: new_title.strip, completed: false }]
    self.new_title = ''
  end
end

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CLI Commands

Command	Description
web_ruby_ui new my_app	Generates a new WebRubyUI project structure
web_ruby_ui dev	Launches a local WebAssembly web server at http://localhost:8000
web_ruby_ui build	Packages standalone index.html for production deployment

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License

MIT License.