PHP for WordPress developers

PHP generators and yield: memory-efficient data processing in WordPress A generator is a function with yield: instead of building a full array and returning it, it hands out one value at a time and pauses until the caller asks for the next one. For WordPress jobs over large data sets (going through all products, exporting…

Pest for WordPress plugin tests Pest is a testing framework on top of PHPUnit with a shorter syntax: tests are closures with a description instead of methods in classes, and expectations read like sentences. For WordPress plugins, it runs on the same WordPress test suite and bootstrap as PHPUnit, so an existing setup can switch…

Debug WordPress with wp-env, Xdebug and PhpStorm @wordpress/env (wp-env) starts a complete WordPress development environment in Docker with one command, with the current plugin or theme mounted inside. It also has Xdebug built in: one flag enables it, and PhpStorm (or VS Code) can then stop at breakpoints in your plugin, step through the code…

PHP Fibers, parallel HTTP requests and background work in WordPress PHP 8.1 added Fibers, and articles promise “concurrency for WordPress” since then. A Fiber is a function that can pause itself and be resumed later; it does not run in parallel with anything. Without an event loop that does non-blocking I/O while fibers wait, they…

PHP 8.4 for WordPress plugin developers PHP 8.4 (November 2024) has two features that change how classes are written, property hooks and asymmetric visibility, a set of small helpers like array_find(), and one deprecation that affects a lot of existing plugin code: implicitly nullable parameter types. A plugin that should run without notices on hosts…

PHP 8.3 for WordPress plugin developers PHP 8.3 (November 2023) is a release of small, practical changes: typed class constants, an #[\Override] attribute, json_validate(), dynamic access to class constants and a few deprecations. In mid-2025 it is the version many hosts recommend, so plugins can start to require it, or at least must run on…

PHP 8.2 in WordPress plugins: readonly classes, DNF types and dynamic properties PHP 8.2 (December 2022) is now the version many hosts offer by default, and it brings one change that produces warnings in old plugin code and three features that make new code cleaner. The warnings come from dynamic properties; the features are readonly…

Upgrade old WordPress plugin code automatically with Rector A plugin written in 2017 for PHP 5.6 still runs, but it is full of array(), missing type declarations, isset( $x ) ? $x : null and string functions that receive null and produce deprecation notices in PHP 8.1. Rector rewrites such code automatically: it parses the…

Add static analysis with PHPStan to WordPress plugin development PHPStan reads PHP code and finds bugs without running it: calling a method on something that can be null or a WP_Error, passing the wrong type to a function, using an undefined variable, a missing array key. It infers types from native declarations, docblocks and function…