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All Glossary Terms/Must-Use Plugin (mu-plugin)
WORDPRESS RELIABILITY GLOSSARY

Must-Use Plugin (mu-plugin)

A high-priority script in wp-content/mu-plugins that runs automatically before standard plugins.

Plain-English Explanation

A special, un-deactivatable background tool that starts before anything else to protect and monitor your website.

Systems Engineering Definition

PHP scripts residing in wp-content/mu-plugins/ that are executed automatically by the WordPress kernel in alphabetical order before normal plugins or themes load.

Common Root Causes
  • •Regular plugins can be deactivated from the admin dashboard; mu-plugins cannot be deactivated or deleted via the UI
  • •Ideal for hosting-level telemetry, security wrappers, and error trapping routines
Autvy Automated Remediation

Autvy operates as a lightweight mu-plugin, guaranteeing that even if all normal plugins crash or the admin dashboard is down, Autvy remains active to protect your site.

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