Liminal: A Browser-Based IDE for Laravel Powered by WebAssembly

Liminal by Andrew Schmelyun is a browser-based IDE that lets you write, run, and preview Laravel applications entirely in the browser — no server setup, no local PHP installation required. It accomplishes this by running PHP 8.4 via WebAssembly.

#What's Included

Once you have it running, you get a full development environment in a single browser tab:

• Code editor — browse and edit files with syntax highlighting for PHP, Blade, JavaScript, TypeScript, JSON, and CSS (powered by CodeMirror 6)
• Preview pane — navigate routes and see rendered HTML output, with Tailwind CSS v4 injected automatically
• Terminal — run Artisan commands with command history
• AI agent — an OpenAI-powered assistant that can read and write files and execute commands on your behalf

#Getting Started

Liminal isn't a Composer package you pull into an existing project. Instead, you clone the repository and build it locally:

git clone https://github.com/aschmelyun/liminal
cd liminal
bun install
cd app
composer install --no-dev --optimize-autoloader
cd ..
bun run build
bun run preview

bun run build packages the Laravel application into public/app.zip, and runs type checking. bun run preview starts a local dev server and opens the IDE in your browser.

#Sharing and Syncing

One of the more interesting features is shareable URLs. File changes are encoded directly into the URL, so you can share a link to a working example that anyone can open immediately in their own browser — no account or installation needed.

For local development, Liminal supports folder sync via the File System Access API, which mirrors the virtual filesystem to a directory on your machine. You can also import directly from a GitHub repository or export your work as a .zip file.

#Limitations

Running PHP in WebAssembly comes with some trade-offs worth knowing about:

• No external network access from PHP code
• The pre-bundled vendor directory cannot be modified
• SQLite only — no MySQL or PostgreSQL
• Performance is slower than native PHP

#Under the Hood

The project is built with Vue 3, TypeScript, Vite, Tailwind CSS v4, and CodeMirror 6. PHP runs in-browser via the @php-wasm/web-8.4 package.

It's an impressive proof of concept for what's possible with WebAssembly in the PHP ecosystem, and a handy tool for quick prototyping, live demos, or sharing reproducible Laravel examples without spinning up a full environment.

You can find the source on GitHub, or give it a try directly at liminal.aschmelyun.com.