How to create a mu-plugin? (must use plugin)

A must use (mu) plugin is like a normal WordPress plugin except you can’t deactivate it.

It runs as soon as you upload it using a FTP client (Filezilla, Transmit, Cyberduck etc.).

To deactivate it, just delete its directory from wp-content/mu-plugins.

Several hooks (including SEOPress ones) must be loaded via a mu-plugin.

It’s also a good alternative if you don’t have a functions.php file.

To create a must use plugin, go to wp-content/mu-plugins directory.

If this folder is not available, add it.

Then create a new file called “seopress-mu.php” (the name doesn’t matter).

Paste this snippet to seopress-mu.php:

And add your own custom code (like actions and filters) to your new mu-plugin.

Test carefully your code! Remember, a mu-plugin is always activated.

You will see your mu-plugin from your WordPress admin, Plugins list, Mu-plugins tab.

Last modified: January 21, 2021