Nestjs & Inversion Of Control(IoC)

Hello friends!
I would like to talk about Nestjs and IoC. First of all I want to point out that I'm not expert of JavaScript world, but I seek for adapting best practice of coding to my js-projects.
Nestjs has a great documentation. I got acquainted with it and I saw lots of benefits of using that one. Installing skeleton is easy. I don't want to waste time on showing it.
Let's get down to describing how to use IoC.
Create a contrived interface:

interface IContrived {
    say():void;
}

Create ContrivedService and implement IContrived interface:

class ContrivedService implements IContrived{
    say():void{}
}

After that to add the service provider for that interface:

const ContrivedServiceProvider: Provider = {
    provide: 'IContrived',//it's an injectable interface 
    useClass: ContrivedService,
};

Add ContrivedServiceProvider into ContrivedModule:

@Module({
    controllers: [],
    providers: [
        ContrivedServiceProvider,
    ],
    imports: [],
})
export class ContrivedModule {}

It's suffice for using IoC with the help of interface. Last step is to inject our interface.
Inject ContrivedService into ContrivedController for instance:

export class ContrivedController {
    constructor(
        @Inject('IContrived')
        private readonly contrivedService: IContrived
    ) {}

This is a simple implementation of IoC and the first step towards achieving fully loose coupled design.
If you have any questions feel free to get in touch with me.

Best regards!