Inertia for Vanilla PHP with Svelte 5

A lightweight implementation of Inertia.js v2 with plain PHP and Svelte 5. No frameworks required.

This version uses Svelte, but there's also a Vue version

Full blog and blog CMS using Inertia, Svelte and SQLite example here

Why?

Modern PHP comes with many powerful features built-in:

• Database connections with PDO
• Session handling
• File system operations
• Array functions and more

This project leverages these capabilities while adding just what you need to build modern SPAs:

• Simple but powerful - Just PHP, a router, and Inertia.js
• No framework overhead - Use PHP's built-in features directly
• Modern UX - SPA-like experience without building a separate API
• Lightweight - Understand your entire codebase without framework complexity
• Svelte 5 Ready - Uses the latest Svelte 5 with Inertia.js v2

Installation

# Clone the repository using degit (no git history)
npx degit dashpilot/inertia-vanilla-php-svelte my-project

# Navigate to project directory and install dependencies
cd my-project
composer install
npm install

Usage

Development

Run both the Vite dev server and PHP server concurrently:

# Start both servers with a single command
npm run dev

This will start:

• PHP development server at http://localhost:8000
• Vite dev server (for assets) at http://localhost:3000

Always access your app through http://localhost:8000

Production

Build your assets for production:

# Build optimized assets
npm run build

Set $isProduction in config.php to true

Then deploy your application to your production server. In production, all assets are served directly from the public/assets directory.

How It Works

1. Use the PHP router to define routes
2. Return page data with Inertia::render('PageName', ['prop' => 'value'])
3. Inertia.js handles client-side page transitions, history, and state

Svelte 5 Implementation

This implementation is specifically configured to work with Svelte 5 and Inertia.js v2, using:

• The new component initialization approach with mount from Svelte
• Modern Inertia directives like use:inertia for links
• Proper TypeScript support (optional)
• Full hot module replacement (HMR) for development

Backend PHP Structure

The PHP backend remains simple and focused:

• A router for defining server routes
• An Inertia adapter class for rendering pages
• Your page controllers/handlers
• Built-in PHP features for everything else

Enjoy the simplicity of vanilla PHP with the power of modern frontend tooling!