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

# PLUGINS

Next, let's talk about plugins. Similar to Redux's meta reducers, we have a plugin interface that allows you to build a global plugin for your state.

All you have to do is call `withNgxsPlugin` with a plugin class. If your plugins have options associated with them, we also suggest defining an injection token.

Let's take a look at a basic example of a logger:

```ts
import { makeEnvironmentProviders, InjectionToken, Injectable, Inject } from '@angular/core';
import { withNgxsPlugin } from '@ngxs/store';
import { NgxsPlugin, NgxsNextPluginFn } from '@ngxs/store/plugins';

export const NGXS_LOGGER_PLUGIN_OPTIONS = new InjectionToken('NGXS_LOGGER_PLUGIN_OPTIONS');

@Injectable()
export class LoggerPlugin implements NgxsPlugin {
  constructor(@Inject(NGXS_LOGGER_PLUGIN_OPTIONS) private options: any) {}

  handle(state: any, action: any, next: NgxsNextPluginFn) {
    console.log('Action started!', state);
    return next(state, action).pipe(
      tap(result => {
        console.log('Action happened!', result);
      })
    );
  }
}

export function withNgxsLoggerPlugin(options?: any) {
  return makeEnvironmentProviders([
    withNgxsPlugin(LoggerPlugin),
    {
      provide: NGXS_LOGGER_PLUGIN_OPTIONS,
      useValue: options
    }
  ]);
}
```

You can also use pure functions for plugins. The above example in a pure function would look like this:

```ts
import { NgxsNextPluginFn } from '@ngxs/store/plugins';

export function logPlugin(state: any, action: any, next: NgxsNextPluginFn) {
  // Note that plugin functions are called within an injection context,
  // allowing you to inject dependencies.
  const options = inject(NGXS_LOGGER_PLUGIN_OPTIONS);

  console.log('Action started!', state);
  return next(state, action).pipe(tap(result) => {
    console.log('Action happened!', result);
  });
}
```

To register a plugin with NGXS, add the plugin to your `provideStore` as an NGXS feature and optionally pass in the plugin options like this:

```ts
export const appConfig: ApplicationConfig = {
  providers: [provideStore([ZooState], withNgxsLoggerPlugin({}))]
};
```


---

# 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 dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://www.ngxs.io/plugins.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.