Intermediate

The object cache API, persistent backends such as Redis, cache groups and invalidation.

Register shortcodes with attributes, return output safely, and when a block is better.

Register post types with the right labels, supports, rewrite rules and REST settings.

Register hierarchical and flat taxonomies, attach them to post types and query by term.

Build custom queries, pagination, ordering, and performance flags such as no_found_rows.

Filter by custom fields and terms, combine conditions, and know when meta queries get slow.

Modify archives and search safely with pre_get_posts instead of extra queries.

Load CSS and JavaScript the WordPress way, with dependencies, versions, defer and conditional loading.

Explore core endpoints, query parameters, embedding, pagination and authentication options.

WordPress from a developer’s view: core, themes, plugins, the database and the block editor.

Register routes, validate and sanitise arguments, check permissions and return proper responses.

Run WordPress locally with tools such as wp-env, Laragon or Local, and enable debugging.

How roles and capabilities work, checking current_user_can, and adding custom capabilities.

What lives in wp-admin, wp-includes and wp-content, and the wp-config.php settings developers change.

The request lifecycle from index.php through plugins, themes, the main query and template loading.

Decide whether code belongs in a theme, a plugin or a must-use plugin, so content survives a theme change.

How actions and filters work, add_action and add_filter, and finding the right hook.

How the Loop displays posts, common template tags, and the main query.

The core tables, how posts, meta, terms and options relate, and why direct SQL is rarely needed.

Control order with priority, accept arguments, remove callbacks, and add hooks to your own code.