WordPress support

WordPress, as a PHP application, can run on PHP WebAssembly. However, there are a few caveats.

SQLite

First, WordPress requires MySQL. However, there isn't a WebAssembly version of MySQL you could run in the browser. WordPress Playground, therefore, ships PHP with the native SQLite driver and leans on SQLite.

But how can WordPress run on a different database?

Behind the scenes, the official SQLite Database Integration plugin intercepts all MySQL queries and rewrites them in SQLite dialect. The x.0 release ships a new WordPress Playground-informed translation layer that allows WordPress on SQLite to pass 99% of the WordPress unit test suite.

WordPress in the browser

WordPress Playground ships a bundled WordPress that you can use in the browser. It's optimized for size, and the installation wizard is run for you.

WordPress in Node.js

In Node.js, you'll typically want to mount WordPress from a disk directory.