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

# Overview

> Zero-React dependency injection for Node, browser, and React Native.

`@brushy/di-core` is the framework-agnostic engine behind `@brushy/di`. It has no React dependency and runs in Node.js, browsers, workers, and React Native.

```bash theme={null}
npm install @brushy/di-core
```

## Quick start

```typescript theme={null}
import { Container, createToken } from "@brushy/di-core";

const LOGGER = createToken<{ log: (msg: string) => void }>("LOGGER");

const container = new Container();
container.register(LOGGER, {
  useValue: { log: console.log },
});

container.resolve(LOGGER).log("ready");
```

## Public exports

### Container

| Export              | Description                                |
| ------------------- | ------------------------------------------ |
| `Container`         | Register and resolve dependencies          |
| `ScopedContainer`   | Explicit scope bucket for manual isolation |
| `ContainerRegistry` | Multi-container / scope registry           |
| `ROOT_SCOPE`        | Sentinel scope constant                    |

### Tokens & providers

| Export         | Description                                   |
| -------------- | --------------------------------------------- |
| `createToken`  | Typed `Symbol` tokens                         |
| `deps`         | Tuple helper for factory dependency inference |
| `defineModule` | Feature modules with inferred tokens          |

### Resolution facades

| Export    | Description                             |
| --------- | --------------------------------------- |
| `resolve` | Resolve via global `containerRegistry`  |
| `inject`  | Global container API (set + resolve)    |
| `server`  | Server singleton container + middleware |

### Request scope

| Export                    | Description                                |
| ------------------------- | ------------------------------------------ |
| `runInRequestScope`       | Sync ALS-bound scope (Node)                |
| `runInRequestScopeAsync`  | Async ALS-bound scope                      |
| `brushyRequestScope`      | Express/Connect middleware                 |
| `getActiveScope`          | Current scope object                       |
| `isRequestScopeSupported` | `true` when AsyncLocalStorage is available |

### Caching & promises

| Export         | Description                       |
| -------------- | --------------------------------- |
| `PromiseCache` | Async method deduplication        |
| `promiseCache` | Global promise cache singleton    |
| `cache`        | General-purpose TTL cache utility |

### Bootstrap & debug

| Export              | Description                              |
| ------------------- | ---------------------------------------- |
| `createBrushyApp`   | Container + `defineModule` shortcut      |
| `enableBrushyDebug` | Expose `globalThis.__BRUSHY_DI__` in dev |
| `getBrushyDebug`    | Read debug API                           |

### Types & errors

| Export                                | Description                                             |
| ------------------------------------- | ------------------------------------------------------- |
| `DependencyError`                     | Missing token / container errors                        |
| `Lifecycle`                           | `"singleton" \| "transient" \| "scoped" \| "immutable"` |
| `ProviderConfig`, `InjectionToken`, … | Provider and token types                                |

### Constants

| Export                         | Description         |
| ------------------------------ | ------------------- |
| `IS_DEV`, `isDev`, `isNodeDev` | Environment helpers |

## Subpath exports

For aggressive tree-shaking, di-core also publishes focused entry points:

```typescript theme={null}
import { Container } from "@brushy/di-core/container";
import { resolve } from "@brushy/di-core/resolve";
import { inject } from "@brushy/di-core/inject";
import { server } from "@brushy/di-core/server";
import { runInRequestScope } from "@brushy/di-core/request-scope";
```

## Documentation map

* [Tokens & providers](/di/di-core/tokens-providers)
* [Lifecycle](/di/di-core/lifecycle)
* [Request scope](/di/di-core/request-scope)
* [Modules](/di/di-core/modules)
* [Container](/di/container): full Container API
* [Server](/di/server): `server` facade