PHP Toolkit

The pieces of WordPress, without the dependencies.

PHP Toolkit is a set of small, pure-PHP libraries for the work that WordPress core does every day — parsing HTML, reading ZIP archives, streaming bytes, importing content, making HTTP requests. No libxml2. No libzip. No curl. No database. Runs on PHP 7.2 through 8.3, on Linux, macOS, Windows, and inside the browser via WordPress Playground.

Quickstart → Take the tutorial Browse components

Where to start

I want to learn the toolkit. Build a real content importer across four short chapters. We'll start with one HTML rewrite and finish with a ZIP-packaged WXR export. Every code block runs in the browser; every chapter ends with something you can keep. ~45 minutes → I'm here to look something up. Eighteen component pages, each with a one-line definition, a minimal runnable example, refinements, the pitfalls people actually trip on, and links back to the tutorial chapters where the concept first appears. Browse all components ↓

The problem

The PHP ecosystem has spent twenty years assuming the host will provide the hard parts. Need to parse HTML? Install libxml2 and reach for DOMDocument. Need a ZIP? Hope ZipArchive is compiled in. Need to fetch a URL? Pray curl is available, then handle the cases where it isn't.

This works fine until it doesn't. Shared hosts disable extensions. WebAssembly runtimes don't have them at all. WordPress Playground runs in your browser and can't shell out to libzip. New PHP releases break old C bindings. Every extension is a dependency that some user, somewhere, can't satisfy.

Meanwhile WordPress core has quietly built its own answers: WP_HTML_Tag_Processor and WP_HTML_Processor for HTML, WP_Block_Parser for the editor's serialized content, hand-rolled archive helpers for plugin and theme updates. Pure PHP, no extensions, written carefully because they have to work everywhere from cheap shared hosting to a Raspberry Pi.

PHP Toolkit lifts those answers out of WordPress and turns them into libraries you can use anywhere.

The shape of it

Eighteen components. Each is a small library focused on one job, distributable as its own Composer package, depending only on PHP itself plus other toolkit components — no Composer packages outside the wp-php-toolkit/* family, no PHP extensions beyond json and mbstring.

All eighteen components

Content and migration

Streams and storage

Networked tools

WordPress runtime support

The toolkit in one line each

preg_replace for HTML→HTML's WP_HTML_Tag_Processor rewrites attributes byte-for-byte without re-serializing. Untouched markup stays byte-identical.
ZipArchive::open()→Zip's ZipFilesystem opens a 2 GB archive using memory proportional to the central directory's size, not the archive's.
file_get_contents on a URL→HttpClient streams the response body, supports Range resume, reports progress, and uses curl when available or PHP stream sockets when it isn't.
DOMDocument::loadHTML→HTML's WP_HTML_Processor parses HTML5 the way browsers do — fragments, implicit tags, the works.
simplexml_load_string→XML's XMLProcessor walks WXR exports as a cursor and rewrites attributes byte-for-byte, never building a full tree.

Credits

Several toolkit components are PHP ports or wrappers of upstream code:

The remaining components — Zip, ByteStream, Filesystem, XML, Encoding, DataLiberation, Git, Merge, HttpClient, HttpServer, CORSProxy, CLI, Blueprints, ToolkitCodingStandards — are toolkit originals, written for this project to fill gaps the PHP ecosystem leaves to extensions.

How the runnable examples work

Most code blocks on this site are <php-snippet> elements from WordPress Playground. Click Run and the page boots a PHP+WordPress runtime in your browser via WebAssembly, unzips the toolkit into it, and executes the snippet. The first run on a page boots the runtime; later runs reuse it. Edit the code in place and click Run again to see what changes.

Static code blocks show shell commands, deployment config, or network-bound code that needs a real local environment.