How To Not Use Dagger2

app-component-1.kt

fun app() = AppComponent.instance

interface AppComponent {
    val context: Context
    val retrofit: Retrofit
    val okHttpClient: OkHttpClient
    val catRepository: CatRepository
    val catService: CatService

    val mainThreadScheduler: Scheduler
    val backgroundThreadScheduler: Scheduler

    companion object {
        lateinit var instance: AppComponent
    }
}

app.kt

fun app() = AppComponent.instance
@Component(modules = [CatModule::class])
interface AppComponent {
    // ... properties

    companion object {
        lateinit var instance: AppComponent
    }
}

class CustomApplication : Application() {

    override fun onCreate() {
        super.onCreate()
        AppComponent.instance =  DaggerAppComponent.builder()...build()
    }
}

dagger-component-1.kt

@Component(modules = [CatModule::class])
interface DaggerComponent {
    fun context(): Context
    fun retrofit(): Retrofit
    fun okHttpClient(): OkHttpClient
    fun catRepository(): CatRepository
    fun catService(): CatService

    @Named("MAIN") fun mainThreadScheduler(): Scheduler
    @Named("BACKGROUND") fun backgroundThreadScheduler(): Scheduler
}

dagger-component-2.kt

@Component(modules = [CatModule::class])
interface AppComponent {
    val context: Context
    val retrofit: Retrofit
    val okHttpClient: OkHttpClient
    val catRepository: CatRepository
    val catService: CatService
    @Named("MAIN") val mainThreadScheduler: Scheduler
    @Named("Background")val backgroundThreadScheduler: Scheduler
}

multiple-components.kt

// Common Module
fun common() = AppComponent.instance
interface CommonComponent {
    val retrofit: Retrofit

    companion object {
        lateinit var instance: CommonComponent
    }
}

interface AppComponent {
    val context: Context
    val retrofit: Retrofit

    companion object {
      lateinit var instance: AppComponent
    }
}

// App Module
fun app() = AppComponent.instance

interface AppComponent {
    val context: Context
    val retrofit: Retrofit

    companion object {
      lateinit var instance: AppComponent
    }
}