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Log4j plugin system is the de facto extension mechanism embraced by various Log4j components.
Plugins make it possible for extensible components to _receive_ feature implementations without any explicit links in between.
It is analogous to a https://en.wikipedia.org/wiki/Dependency_injection[dependency injection] framework, but curated for Log4j-specific needs.

In a nutshell, you annotate your classes with link:../javadoc/log4j-core/org/apache/logging/log4j/core/config/plugins/Plugin.html[`@Plugin`] and their (`static`) factory methods with link:../javadoc/log4j-core/org/apache/logging/log4j/core/config/plugins/PluginFactory.html[`@PluginFactory`].
Last, you inform the Log4j plugin system to discover these custom classes.
This is done using running the link:../javadoc/log4j-core/org/apache/logging/log4j/core/config/plugins/processor/PluginProcessor.html[`PluginProcessor`] annotation processor while building your project.
Refer to xref:manual/plugins.adoc[] for details.
