> For the complete documentation index, see [llms.txt](https://docs.zongsoft.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.zongsoft.com/documentation/en/framework/plugins.md).

# Plugin Framework

Responsibilities and core concepts of Zongsoft.Plugins plugin framework.

![Plugin Framework](https://1509929121-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FVtPQeWxVwz4p7FTcxkG8%2Fuploads%2Fgit-blob-9196bec8b8df6c12712d5b0dd515deeb0d57f7cf%2Fzongsoft-plugins-cover.png?alt=media)

[`Zongsoft.Plugins`](https://github.com/Zongsoft/framework/tree/main/Zongsoft.Plugins) is the core library for Zongsoft plugin-based applications. It divides an application into plugin modules that can be deployed independently, declare dependencies, and attach capabilities to extension points. Terminal programs, background services, Web applications, and rich clients share the same extension model.

## Core Concepts

* Plugin manifest: A `*.plugin` file describes assemblies, dependencies, builtins, resolvers, and extension points.
* Plugin directory: By default, the host scans the `plugins/` directory under the application directory at startup.
* Plugin tree: Extension points are organized into a tree of paths, such as `/Workbench/Data/Drivers`.
* Builtin: A buildable object on the plugin tree, created or exposed by builders such as `object`, `lazy`, and `expose`.
* Application context: The runtime context representing the application, environment, modules, services, events, and [workers](https://github.com/Zongsoft/framework/blob/main/Zongsoft.Core/src/Components/IWorker.cs).
* [Application module](https://github.com/Zongsoft/framework/blob/main/Zongsoft.Core/src/Services/IApplicationModule.cs): A business or infrastructure boundary explicitly defined and mounted by the application. It can have its own service domain and event registry; modules do not automatically correspond one-to-one with plugins.

## Relationship with Host

The host establishes the .NET Host, configuration sources, and service container. It is distinct from a business module. The plugin framework loads manifests from `plugins/`, and the plugins register business capabilities with the application.

```mermaid
flowchart LR
	A["Hosts"] --> B["plugin framework"]
	B --> C["plugins directory"]
	C --> D["*.plugin"]
	D --> E["plugin tree"]
	E --> F["Modules/Services/Commands/Events/API"]
```

## Loading Results

After loading plugins, the runtime contains three layers:

* Plugin collection: Records the loaded master, slave, and child plugins.
* Plugin tree: Mounts extension points, builtins, and custom objects at unified paths.
* Service container: Registers services from host and plugin assemblies in the application service container.

The default foundational plugins mount nodes such as `/Workbench`, `/Workbench/Configuration/ConnectionSettings`, and `/Workbench/Diagnostics`. Data, Web, security, and other plugins extend these nodes with drivers, filters, commands, event handlers, and services.

## Roles and Responsibilities

{% tabs %}
{% tab title="application developer" %}
Focus on the capabilities a plugin provides: services, commands, Web APIs, background [workers](https://github.com/Zongsoft/framework/blob/main/Zongsoft.Core/src/Components/IWorker.cs), data drivers, or business modules. Understanding the plugin directory and deployed artifacts is usually sufficient.
{% endtab %}

{% tab title="Plugin author" %}
Focus on how `*.plugin` files declare assemblies, dependencies, builtins, and extension points. Plugin authors need to understand plugin tree paths and builtin resolvers.
{% endtab %}

{% tab title="host maintainer" %}
Focus on host startup, configuration loading, plugin directory locations, service registration, and diagnosis of plugin-loading failures.
{% endtab %}
{% endtabs %}

## Further Reading

Before writing manifests, explore the [Plugin Design Essays](/documentation/en/overview/pluginization.md#plugin-design-essays) to clarify module ownership, extension contracts, and delivery responsibilities.

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref">Page</th></tr></thead><tbody><tr><td><strong>Plugin Application Model</strong></td><td>The relationship between hosts, application contexts, modules and services.</td><td><a href="/documentation/en/framework/plugins/application-model.md">Plugin Application Model</a></td></tr><tr><td><strong>Plugin Manifests and Loading</strong></td><td>plugin manifest, dependencies, extension point and loading strategy.</td><td><a href="/documentation/en/framework/plugins/plugin-file.md">Plugin Manifests and Loading</a></td></tr><tr><td><strong>Host Integration</strong></td><td>Launch plugin-based applications in the .NET Host.</td><td><a href="/documentation/en/framework/plugins/hosting.md">Host Integration</a></td></tr><tr><td><strong>Builtins and Services</strong></td><td>builder, resolver, plugin tree paths and service discovery.</td><td><a href="/documentation/en/framework/plugins/builtins-and-services.md">Builtins and Services</a></td></tr></tbody></table>

## Related Resources

* [Zongsoft.Plugins source code directory](https://github.com/Zongsoft/framework/tree/main/Zongsoft.Plugins)
* [Zongsoft.Plugins README](https://github.com/Zongsoft/framework/blob/main/Zongsoft.Plugins/README.md)
* [Zongsoft.Plugins NuGet package](https://www.nuget.org/packages/Zongsoft.Plugins)
* [framework repository](https://github.com/Zongsoft/framework)


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.zongsoft.com/documentation/en/framework/plugins.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.