> ## Documentation Index
> Fetch the complete documentation index at: https://docs.webarchery.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Resolve Application Services with the IoC Container

> Bind transient, singleton, eager, named, and existing services; resolve them safely, create child scopes, and register asynchronous cleanup callbacks.

The Archery IoC container owns application services and their lifetimes; you will register dependencies, resolve them, isolate scopes, and clean them up.

## Register services

Use `bind` for a new value on every resolution, `singleton` for one value per scope, and `bindInstance` for an object you already created. Factory callbacks receive the container and optional runtime options.

```dart lib/src/providers/aws/s3_client_provider.dart theme={null}
base class S3ClientProvider extends Provider {
  @override
  Future<void> register(ServiceContainer container) async {
    final s3Config = S3Config.fromMap(App().config.get('env.aws'));
    final s3Client = S3Client(s3Config, debug: true);
    container.bindInstance<S3Client>(s3Client);
  }
}
```

```dart example/main.dart theme={null}
final config = await AppConfig.create();
app.container.singleton<AppConfig>(
  factory: (_, [_]) => config,
  eager: true,
);
```

## Resolve and inspect

```dart lib/src/http/routes/web.dart theme={null}
final router = app.make<Router>();
final config = app.container.make<AppConfig>();
final optionalClient = app.container.tryMake<S3Client>();

if (app.container.contains<AppConfig>()) {
  print(app.container.listRegistrations());
}
```

`make<T>()` throws `ServiceContainerException.registrationNotFound` when no binding exists. Use `tryMake<T>()` when absence is expected. Pass `name` to registration and resolution methods when you need several implementations of one type.

## Manage lifecycle

Call `initialize()` to construct eager singletons and `allReady()` to await tracked asynchronous initialization. Register cleanup with `onDispose()` and call `dispose()` to run callbacks in reverse order.

```dart lib/src/bootstrap.dart theme={null}
container.onDispose(() async {
  await sqliteDatabase.close();
});
```

<Note>
  `newScope()` inherits parent bindings but keeps its own singleton instances, which makes it suitable for request or feature isolation.
</Note>