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nextflow/docs/developer/nextflow.plugin.md

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+
+# `nextflow.plugin`
+
+The `nextflow.plugin` package implements the plugin manager.
+
+## Class Diagram
+
+```{mermaid} diagrams/nextflow.plugin.mmd
+```
+
+```{note}
+Some classes may be excluded from the above diagram for brevity.
+```
+
+## Notes
+
+The plugin system uses the [PF4J](https://pf4j.org/) library, which allows for extension classes to be loaded at runtime. Each plugin includes a manifest of extension classes, all of which extend or implement some base class in Nextflow. The `Plugins` class can be used to query the available extensions for a given base class. Extensions can be assigned a priority using the `@Priority` annotation, to ensure that certain extensions are used over others when available.