Technote
The grammar of extending WordPress — changing behaviour without touching core or the theme, and the classic ways hooks go wrong.
8 articles
Development workflow Intro
add_action and add_filter write into the same registry. Only one thing separates them: a filter must return a value, and one that forgets silently nulls the thing it…
Development workflow Intro
The same code on the same hook behaves differently depending on when it runs. Taxonomies, post types and translations all see an incomplete world before init.
Development workflow Practical
Priority is a queue position, not authority. Raising your number is a move the other side can also make, and jumping behind a translation filter sends the untranslated…
Development workflow Practical
This hook fires for every WP_Query — menus, widgets and admin list tables included. Without guards, screens you never meant to touch change quietly.
Development workflow Practical
One filter, two different strings depending on whether you sit at priority 1 or 12. Pick the wrong side and your pattern simply never matches.
Development workflow Practical
remove_action says nothing when it fails, and a wrong name, a wrong priority and running too early all look identical. Checking the return value is half the fix.
Development workflow Advanced
Code with no extension points gets forked or edited in place. Where you put do_action and apply_filters — and how many — decides how long that code survives.
Development workflow Advanced
A callback that never runs, one that runs and gets overwritten, and a hook that never fires are three different problems. Reading the registry separates all three at…