Nextcloud Playground

Nextcloud Playground runs a full Nextcloud server entirely in the browser using WebAssembly. There is no backend: PHP, the Nextcloud application, and its SQLite database all execute inside your browser tab on the @php-wasm runtime — the same PHP-in-WebAssembly engine that powers WordPress Playground.

It is a sibling of the Moodle, Omeka S, and FacturaScripts playgrounds, sharing the same shell → service worker → PHP worker → @php-wasm architecture.

Status: the Phase-0 feasibility spike proved that Nextcloud 31.0.14 installs against SQLite and serves its login page under php-wasm (PHP 8.3) with a small set of source patches and a posix polyfill. See feasibility-spike.md for the proven approach and constraints. The remaining hard problem is bundle size / browser memory.

Try it

• Online: open the hosted GitHub Pages build (the live demo link in the repository).
• Locally: make up, then open http://localhost:8085/.

Default credentials are admin / admin. After boot you land on the login page (/index.php/login) or, with autologin enabled, directly on the dashboard.

Use this documentation to

• Get started — try it online or run it locally.
• Understand the architecture and build — shell, runtime, the ZIP bundle, the occ install, and how to add a Nextcloud version.
• Write a blueprint — the declarative JSON that provisions users, groups, apps, config, files and shares via occ.
• Know the limits — features that are dead or degraded under WebAssembly.
• Read the feasibility spike — the single most important reference: the proven patch set and constraints.

How it works (one paragraph)

The shell page hosts an iframe whose requests are intercepted by a service worker and routed to a PHP worker. The worker boots a @php-wasm PHP 8.3 runtime, extracts a trimmed, readonly Nextcloud core bundle into the in-memory filesystem (MEMFS), installs Nextcloud against SQLite via occ maintenance:install, applies a blueprint, and serves the web UI back into the iframe. A posix polyfill plus a five-patch source set (all gated on PHP_SAPI === 'wasm') make Nextcloud's PHP run in this sandbox. Mutable state lives in browser persistence and is ephemeral by default.

Supported versions

Nextcloud majors 30, 31 (default), and 32, all built against php-wasm PHP 8.3. See src/shared/nextcloud-versions.js.

Useful links

• Nextcloud: https://nextcloud.com/
• Nextcloud server source: https://github.com/nextcloud/server
• WordPress Playground (architecture / @php-wasm): https://wordpress.github.io/wordpress-playground/