koinSetup

val retrofit = module(override = true) {
    single {

        val interceptor = HttpLoggingInterceptor()
        if (BuildConfig.DEBUG) {
            interceptor.apply { interceptor.level = HttpLoggingInterceptor.Level.BODY }
        } else {
            interceptor.apply { interceptor.level = HttpLoggingInterceptor.Level.NONE }
        }

        val client = OkHttpClient.Builder()
            .addInterceptor(interceptor).build()

        Retrofit.Builder()
            .baseUrl(Utils.BASE_URL)
            .addConverterFactory(GsonConverterFactory.create())
            .client(client)
            .build()
    }
}

val authClient = module {
    single {
        val interceptor = HttpLoggingInterceptor()
        if (BuildConfig.DEBUG) {
            interceptor.apply { interceptor.level = HttpLoggingInterceptor.Level.BODY }
        } else {
            interceptor.apply { interceptor.level = HttpLoggingInterceptor.Level.NONE }
        }
        OkHttpClient.Builder().addInterceptor(AuthInterceptor()).addInterceptor(interceptor).build()
    }
}

val authRetrofit = module {
    single {
        Retrofit.Builder()
            .baseUrl(Utils.BASE_URL)
            .client(get())
            .addConverterFactory(GsonConverterFactory.create())
            .build()
    }
}

module(override = true) is not necessary - if the project doesn't have multiple modules, or the base url doesn't change

Noted. Thanks for pointing this out