@nexusdi/decorators

Accelerate your development with a declarative, visual syntax for dependency injection.

Manual dependency lists in static deps can become tedious and visually disconnected from the constructor they support. @nexusdi/decorators solves this by providing a high-level, declarative syntax that mirrors the style of NestJS while remaining compatible with standard TypeScript decorators.

Key Features

These decorators utilize standard TC39 specifications to avoid restrictive compiler settings.

• Standard Decorators: No experimentalDecorators or emitDecoratorMetadata required in tsconfig.json.
• Broad Compatibility: Works with tsc, TypeScript 7, esbuild, SWC, Babel, Bun, Deno, and Vite with its Babel plugin. Plain Vite and Node's type stripping cannot run these decorators.
• Declarative Toolset:
  • @Injectable({ deps }): Defines constructor dependencies.
  • @Inject(TOKEN): Enables dependency injection via accessor fields.
  • @Module({ ... }): Converts a class into a NexusDI module.

Installation

0.4 is a release candidate on the npm next tag. Install every @nexusdi package from next so their versions match. Without @next, npm installs core 0.3 and stops with a peer conflict.

npm install @nexusdi/decorators@next @nexusdi/core@next

Quick Example

import { Nexus, Token, provide } from '@nexusdi/core';
import { Injectable, Module } from '@nexusdi/decorators';
import { Inject } from '@nexusdi/decorators';

interface IBridge {
  readonly callsign: string;
}

const CALLSIGN = new Token<string>('Callsign');
const BRIDGE = new Token<IBridge>('Bridge');
const HELM = new Token<IBridge>('Helm');

@Injectable({ deps: [CALLSIGN] })
class Bridge implements IBridge {
  constructor(readonly callsign: string) {}
}

// Field injection: @Inject on an accessor field.
class Helm implements IBridge {
  @Inject(CALLSIGN) accessor callsign!: string;
}

@Module({
  providers: [
    provide(CALLSIGN, { useValue: 'Meridian' }),
    provide(BRIDGE, { useClass: Bridge }),
    provide(HELM, { useClass: Helm }),
  ],
})
class Command {}

await using ship = await Nexus.create(Command);
ship.get(BRIDGE).callsign; // -> 'Meridian'
ship.get(HELM).callsign; // -> 'Meridian'

Documentation

• Decorators Guide
• Documentation
• Examples
• NexusDI on GitHub

License

MIT